FJ60 A/C and overheat help (1 Viewer)
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the above is what the dual fan setup from a ford v6 contour looks like. Notice how the fans cover the entire radiator core..this setup cam off and the GM fan setup went on. Go the GM fan clutch and matching fan route...and your issues will be solved. That nice radiator you see in the pic cracked about 1.5yrs later....not a happy camper on that $$$.
I have a winch on my truck and the a/c is functional...
I have a winch on my truck and the a/c is functional...
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Elbert - respectfully unless you have used the same engine, cam, timing, and Radiator how can you say for certain anything will work ? And perhaps you have and I missed that part.
There is quite a difference between a Gen II 5.7 and a Gen I ( I assume) stroker engine. He might even have a cracked head or block or bad head gasket or other issues.
I do think it is an undersized Radiator, but there are quite a few variables to be eliminated before hand at no cost. At least in my opinion.
There is quite a difference between a Gen II 5.7 and a Gen I ( I assume) stroker engine. He might even have a cracked head or block or bad head gasket or other issues.
I do think it is an undersized Radiator, but there are quite a few variables to be eliminated before hand at no cost. At least in my opinion.
I don't think we are talking about cooling some radical hot-rot setup..
Have you bothered to read through the various engine swap threads on this board, or the endless threads on electric fans on v8 swaps.
How can I say what I did....experience....time served....experimentation, real world screwing around...(thats how)... not arguing with you..
Have I tried the dual electric fans..yes
Have I tired other electric fans ...yes
Have I read various other threads on similar question..yes
did I suggest a 4 core radiator..yes
am I running the setup I suggested..yes
What other insight do you have in this specific v8 swap? Just as you have your view I have mine...I have the courtesy to simply offer up my opinion. If you want to debate that feel free.
Why yes there could be many cooling issues....at hand. DO you assume otherwise that the fan setup is capable? A v8 swap is a problem child to start with....we could go on for days about cracked heads, blown head gasket, timing out of whack, distributor issues, blocked radiator or blocked air-way, clogged exhaust..etc. ** One assumes the obvious issues are dealt with and the poster is concerned about the "mechanics" of the V8 swap setup...or at least that my take.
I'm not throwing darts at the OP or anyone else, we are all taking educated guesses at pictures and what someone has described and or posted in pics. Am I aware there are issues to resolve in a normal OEM vehicle that overheats...yes. This is a V* swap with a 383...that one assumes is good and has no other mechanical issues and timing is good etc. Given all of that.. I stand by what I said...
My assumption is that the OP is concerned about his cooling setup on his V8 Swap truck...I offered a suggestion. You and or others may choose not to go down that road. There may be other issues in play that we don't have enough information at present to evaluate, on initial presentation I offered some pictures and some solutions to a V8 Swap cooling setup, of which has been debated over and over on this board.
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No I have not read all the threads here on engine swaps, I have read a few.
I have 40 plus years experience fxxxing around with engine swaps, hot rods, Scouts, Jeeps, low buck round dirt track cars, tractors and god knows what else. And all I have are informed opinions, and an idea about what Might work. And unless I have done it with the same components in the same condition experience has taught me not to say for certain that something Will work until I Have Done it.
I have 40 plus years experience fxxxing around with engine swaps, hot rods, Scouts, Jeeps, low buck round dirt track cars, tractors and god knows what else. And all I have are informed opinions, and an idea about what Might work. And unless I have done it with the same components in the same condition experience has taught me not to say for certain that something Will work until I Have Done it.
Nice edit job Elbert.
The two successful swaps that I have done closest the one we are addressing here are a SBC 383 into a Cj-5 backed by a SM420 and Dana 20 with no A/C; and a 415 SBC Into a 65 Wagoner with A/C and a TH400, that had a performance cam and around 9.5/1
Compression. The CJ has run cool since 1983, even in some serious of road flogging. It has stock CJ7 tanks with a 4 row core added, fabbed shroud with fan and fan clutch sourced from a '77 chevy 1 Ton.
The other one was tougher, it required a Big Block Vette radiator, fan and clutch, and a pusher electric fan for low speed supplemental cooling in only moderate off road use.
I think your solution will probably work; but a reverse cooled Vortec is quite different than a Gen I SBC.
Compression. The CJ has run cool since 1983, even in some serious of road flogging. It has stock CJ7 tanks with a 4 row core added, fabbed shroud with fan and fan clutch sourced from a '77 chevy 1 Ton.
The other one was tougher, it required a Big Block Vette radiator, fan and clutch, and a pusher electric fan for low speed supplemental cooling in only moderate off road use.
I think your solution will probably work; but a reverse cooled Vortec is quite different than a Gen I SBC.
settle down.... you are calling me out for saying a solution works? really... well? thats nice.
As stated I've done what I said. It works. I"ve tried alternative cooling solutions that did not work as well.
I offered a solution that works....you may take that any way you like.
I stated that I have a V8 Cooling solution that works.....if you think I'm off base because the OP is running a 383...well then, I make no apology. What I said does work and its been demonstrated etc. Could there be underlying issues...yes..no-one said differently, could there be other factors we don't know..yes.
Get Real!...
As stated I've done what I said. It works. I"ve tried alternative cooling solutions that did not work as well.
I offered a solution that works....you may take that any way you like.
I stated that I have a V8 Cooling solution that works.....if you think I'm off base because the OP is running a 383...well then, I make no apology. What I said does work and its been demonstrated etc. Could there be underlying issues...yes..no-one said differently, could there be other factors we don't know..yes.
Get Real!...
yeah..I get on a edit game at times.
I'm just saying my solution is valid...period any of us can throw logic bombs on most posts here...myself included.
no further comment on this line of argument from me...back to the solutions to help the OP
I'm just saying my solution is valid...period any of us can throw logic bombs on most posts here...myself included.
no further comment on this line of argument from me...back to the solutions to help the OP
If it doesn't work can the OP send you the Bill ?
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I think a good solution to the V8 swap game is to use a radiator out of a 3/4 ton GM truck. But then you get into all kind of fabrication issues. FJ60 Grill area is limited, the battery or dual batteries are right there by the radiator. Just not a lot of grill area to allow for major air flow, and then problems adapting to a larger radiator are issues.
while not trying to stand on the mountain, and in realization that there is more that one valid approach. What I have suggested is a reasonable approach if you want to retain your stock radiator setup. Get the 4 core OEM style replacement radiator, go with the GM fan clutch and fan that matches your version or configuration of your SBC. There may be many...many variables in the mix...(that a given) to include unknowns that the OP may not be aware of. So take my suggestion as a workable solution....
There are many paths to a cooling solution...not all of them work and there are sometimes multiple solutions that work, and some of that depends on fabrication skills and how much $$ you want to throw in the mix. I suggested a proven solution, take my suggestion as an attempt to save yourself from pain and suffering with chasing some of the other solutions that have been unproven or proven to be marginal. I offered a suggestion in good faith..that is all!
while not trying to stand on the mountain, and in realization that there is more that one valid approach. What I have suggested is a reasonable approach if you want to retain your stock radiator setup. Get the 4 core OEM style replacement radiator, go with the GM fan clutch and fan that matches your version or configuration of your SBC. There may be many...many variables in the mix...(that a given) to include unknowns that the OP may not be aware of. So take my suggestion as a workable solution....
There are many paths to a cooling solution...not all of them work and there are sometimes multiple solutions that work, and some of that depends on fabrication skills and how much $$ you want to throw in the mix. I suggested a proven solution, take my suggestion as an attempt to save yourself from pain and suffering with chasing some of the other solutions that have been unproven or proven to be marginal. I offered a suggestion in good faith..that is all!
stupid is all I have to say
Well you said it would "work".
Then you made a very reasoned thought out post.
Then you made a very reasoned thought out post.
no need to further muddy up the water on a useless discussion/debate... we can can debate what works in another thread...or you can come find me on some ride and we can debate whatever. I say my chevette is faster than your vega...now what?
I say before the original poster drops a s***load of money on another radiator and fans he should consider eliminating a few things first. Such as removing anything that impedes flow through the existing setup, get it up to speed turn on the A/C and see if the temperature is OK. My guess is it won't be, but this will take the speculation out of it. If it works, then add a fan and fan clutch from a similar Truck application and supplemental fans if he wants. If it doesn't work then go with a radiator with more cooling capacity. You will know what works when it works for your setup, climate, driving conditions etc. It may be a long path.
Separate from the above check for proper water flow, timing, gas leakage into coolant etc. - it costs little and you just might find a problem and save yourself some heart ache.
I didn't learn this from one or two experiences but from dozens.
Separate from the above check for proper water flow, timing, gas leakage into coolant etc. - it costs little and you just might find a problem and save yourself some heart ache.
I didn't learn this from one or two experiences but from dozens.
Asmodian your 383 probably has 80-100
More Horse power over your old 350, there is a direct correlation between Horse Power and Heat you must get rid of. If you haven't already done so ask the manufacturer of your Radiator what they rate it for. Off Road vehicles are more difficult to cool when offroading slower speeds operating in lower gears low range mud sand hills and so on, so discount accordingly.
Reverse flow engines are a little bit easier to cool, IMO.
More Horse power over your old 350, there is a direct correlation between Horse Power and Heat you must get rid of. If you haven't already done so ask the manufacturer of your Radiator what they rate it for. Off Road vehicles are more difficult to cool when offroading slower speeds operating in lower gears low range mud sand hills and so on, so discount accordingly.
Reverse flow engines are a little bit easier to cool, IMO.
- Thread starter
- #37
Ok folks- to clear up any missed detail on the setup from earlier:
Engine - brand new crate motor from blueprint engines, <200 miles on it
They don't have a HP rating for this on the site but I have an inquiry out to them to see if they do.
So - there really is no "donor" vehicle who's cooling setup I can try to emulate... this motor is not an OEM spec setup.
Here are dyno results from motor:
And, the spreadsheet:
I've decided to get an 18" clutch fan setup and give that a shot with a fabricated shroud. Keep an eye out on ebay for a brand new Flex-a-lite fan and thermo-relay setup if it works... unless the garage will take them back (doubt it)
.
Fan and clutch I selected are supposed to match an 87-95 GM 350... my motor has the same setup as engines from that period.
If that doesn't show a marked improvement then I'll have to entertain a larger radiator... One thing that I know for certain is - right now my low-road-speed airflow is nowhere near as much as it should be. The fan is not flush with the radiator core, and is only covering about 60% of the overall surface. Even with this suboptimal airflow, the truck runs at non-dangerous temperatures. I had it out in 90 degree heat in stop and go traffic and it wandered around the 220-230 range. Given this cooling performance while utilizing little more than half of the radiator and very likely under 2500 CFM across a little more than half the fins, I am willing to bet the radiator is up to it and I need more airflow.
Anybody ever heard of new motors running a few degrees hotter during initial break-in period?
Another thing I know for certain is that if I drop another grand into the brand-new-motor, my girlfriend will probably set fire to the thing and walk out of here.
Engine - brand new crate motor from blueprint engines, <200 miles on it
Cam .480 Int / .486 Exh & 229 Int / 230 Exh duration @ .050
9.5 : 1 compression
Fuel injection is via Edelbrock Pro-Flow gen 1 (tuned by the shop who installed the motor)
Radiator (brand new) from cruisercorps: http://www.cruisercorps.com/engine/cooling/radiators/radiator-fj60-fj62-1981-1990-3-row.html9.5 : 1 compression
Fuel injection is via Edelbrock Pro-Flow gen 1 (tuned by the shop who installed the motor)
They don't have a HP rating for this on the site but I have an inquiry out to them to see if they do.
So - there really is no "donor" vehicle who's cooling setup I can try to emulate... this motor is not an OEM spec setup.
Here are dyno results from motor:
And, the spreadsheet:
I've decided to get an 18" clutch fan setup and give that a shot with a fabricated shroud. Keep an eye out on ebay for a brand new Flex-a-lite fan and thermo-relay setup if it works... unless the garage will take them back (doubt it)
.Fan and clutch I selected are supposed to match an 87-95 GM 350... my motor has the same setup as engines from that period.
If that doesn't show a marked improvement then I'll have to entertain a larger radiator... One thing that I know for certain is - right now my low-road-speed airflow is nowhere near as much as it should be. The fan is not flush with the radiator core, and is only covering about 60% of the overall surface. Even with this suboptimal airflow, the truck runs at non-dangerous temperatures. I had it out in 90 degree heat in stop and go traffic and it wandered around the 220-230 range. Given this cooling performance while utilizing little more than half of the radiator and very likely under 2500 CFM across a little more than half the fins, I am willing to bet the radiator is up to it and I need more airflow.
Anybody ever heard of new motors running a few degrees hotter during initial break-in period?
Another thing I know for certain is that if I drop another grand into the brand-new-motor, my girlfriend will probably set fire to the thing and walk out of here.
You have a strong running Engine, and a much more heat to dissipate than what was in it before, and cooling it for off-road use is going to be a challenge; be happy you don't have an Automatic then you would have even a bigger problem. 
Yes new engines will run a little warmer during break in, but not enough to cause much of a problem if everything else is right, by 500-1000 miles it should stabilize.
Your Fan and Fan Clutch sound like a good place to start to me. If you haven't ordered already check the specs on components on a 1 ton truck from 87-95 era, that is just my advice.
Placement of the Fan within the shroud is critical, the gap between the outside of the fan and the shroud should be minimal, but you must allow for the engine flexing in the mounts, so I would shoot for 3/4 inch clearance. The blades should be half to 2/3 thirds covered by the shroud, you can get a little more cooling by the use of spacers to adjust this dimension.
There are so many other variables, some Aluminum Radiators are designed for High Volume Water Pumps, and sometimes High Volume Water Pumps are part of the problem, is your water pump pulley 1:1 ? Or is it a higher numeric ratio ? Is your Timing retarded ? If you engine comes on strong is probably OK, but it would be nice to know the advance curve. It might be worth you trouble to have the Radiator tested for the presence of Hydro-Carbons, to eliminate bad head, block, gasket problems. Any good shop should be able to do this very inexpensively. Do you know for certain your Thermostat is working correctly ? Are you getting enough flow thru your Radiator ? There is a great thread in the 60s FAQ section on overheating that covers the problems you might have. Just because parts are new, doesn't always mean that they work properly, or that you were sold the part you ask for.
And Elbert gave you some great advice, my only difference with it is saying for certain it will work, instead of it may work, being your setup is quite different from his.
One last thing - ask Blueprint Engines for their advice, they should very knowledgeable professionals who work with problems like this day in and day out.
All the best !
Yes new engines will run a little warmer during break in, but not enough to cause much of a problem if everything else is right, by 500-1000 miles it should stabilize.
Your Fan and Fan Clutch sound like a good place to start to me. If you haven't ordered already check the specs on components on a 1 ton truck from 87-95 era, that is just my advice.
Placement of the Fan within the shroud is critical, the gap between the outside of the fan and the shroud should be minimal, but you must allow for the engine flexing in the mounts, so I would shoot for 3/4 inch clearance. The blades should be half to 2/3 thirds covered by the shroud, you can get a little more cooling by the use of spacers to adjust this dimension.
There are so many other variables, some Aluminum Radiators are designed for High Volume Water Pumps, and sometimes High Volume Water Pumps are part of the problem, is your water pump pulley 1:1 ? Or is it a higher numeric ratio ? Is your Timing retarded ? If you engine comes on strong is probably OK, but it would be nice to know the advance curve. It might be worth you trouble to have the Radiator tested for the presence of Hydro-Carbons, to eliminate bad head, block, gasket problems. Any good shop should be able to do this very inexpensively. Do you know for certain your Thermostat is working correctly ? Are you getting enough flow thru your Radiator ? There is a great thread in the 60s FAQ section on overheating that covers the problems you might have. Just because parts are new, doesn't always mean that they work properly, or that you were sold the part you ask for.
And Elbert gave you some great advice, my only difference with it is saying for certain it will work, instead of it may work, being your setup is quite different from his.
One last thing - ask Blueprint Engines for their advice, they should very knowledgeable professionals who work with problems like this day in and day out.
All the best !
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here is what you will shortly discover. You have only "X" amount of room between your water pump and the radiator, your bolt in solutions are limited regardless of the SBC in question, there are a number of threads on the board that will offer you insight into previous work that others have done and proven solutions. What is clear some trucks never get into 4wd and never go off road and may or may not have A/C that is functional. And then finally it depends on how much $$ you want to spend and can you do the work yourself in regard to fabrication skills. THe stock type radiator only has so much square inches of radiator core exposed to the airflow out of a very small grill area (as compared to a 1/2 or 3/4 ton GM pickup)...what that means is that your bolt in radiator solution will only exchange so much heat.
I believe one person swapped in a radiator out of a 92 z28 and said it worked well.
Excluding all the common issues related to overheat. A V8 swap in a FJ60 is a cooling challenge to start with. I would have put a GM 3/4 ton radiator in my 60 at day one of the swap...but thats not just a simple operation and it impacts various other things under the hood, which I did not want to change at the time.
OF your "bolt in solutions"
The 4 core OEM style radiator is a proven solution
A custom / fabericated fan shroud is proven solution (many variations on that)
The GM fan clutch and fan is a proven solution (different variations on that, depending on year and model of 5.7)
A 383 was never produced and sold in GM trucks and you may or may not have some custom brackets, but in all likelihood the front of the 383 SBC has some common brackets off a similar 5.7. Even the fan clutches through the SBC production do not interchange and mate up with all the possible fan combinations.
The most effective cooling solution I'm aware of is what I shared with the pics. With stock items in place regarding the radiator and condensor.
Again if you want a bolt in solution you have some very finite solutions. You have space issues about every which way you turn under the hood, you are limited on space between the engine and radiator, and then between the radiator and condensor, and then from left and right and top to bottom in respect to the radiator and available options to transplant another radiator without major alterations. One assumes you want the A/c to function and the condensor left in stock location etc.
So...there are many things to entertain and consider but in the end....when you are talking about a bolt in solution ...irrespective of engine, you have very limited choices.
Cooling stock GM SBC has some challenges, but given the options in the mix and cooling any v8 has about the same set of solutions within reason on these trucks, due to the issues I mentioned abovve. Yes you could chop and cut and make something work but that all depends on how far you are willing to modify the truck and then fab skills and $$ and how much you are willing to alter other systems on the truck to make that happen.
If you want the stock components to stay where they are (radiator and a/c condenser) then the solution I suggested is the most effective one I'm aware of and it works. I've not seen a more effective solution leaving stock type radiator and condenser in place. There may be others....I've not seen it or read about or experienced it.
Another thing to check is that if your engine ceterline sits square with the raditor core..ie does the water pump sit square with the radiator core.
I believe one person swapped in a radiator out of a 92 z28 and said it worked well.
Excluding all the common issues related to overheat. A V8 swap in a FJ60 is a cooling challenge to start with. I would have put a GM 3/4 ton radiator in my 60 at day one of the swap...but thats not just a simple operation and it impacts various other things under the hood, which I did not want to change at the time.
OF your "bolt in solutions"
The 4 core OEM style radiator is a proven solution
A custom / fabericated fan shroud is proven solution (many variations on that)
The GM fan clutch and fan is a proven solution (different variations on that, depending on year and model of 5.7)
A 383 was never produced and sold in GM trucks and you may or may not have some custom brackets, but in all likelihood the front of the 383 SBC has some common brackets off a similar 5.7. Even the fan clutches through the SBC production do not interchange and mate up with all the possible fan combinations.
The most effective cooling solution I'm aware of is what I shared with the pics. With stock items in place regarding the radiator and condensor.
Again if you want a bolt in solution you have some very finite solutions. You have space issues about every which way you turn under the hood, you are limited on space between the engine and radiator, and then between the radiator and condensor, and then from left and right and top to bottom in respect to the radiator and available options to transplant another radiator without major alterations. One assumes you want the A/c to function and the condensor left in stock location etc.
So...there are many things to entertain and consider but in the end....when you are talking about a bolt in solution ...irrespective of engine, you have very limited choices.
Cooling stock GM SBC has some challenges, but given the options in the mix and cooling any v8 has about the same set of solutions within reason on these trucks, due to the issues I mentioned abovve. Yes you could chop and cut and make something work but that all depends on how far you are willing to modify the truck and then fab skills and $$ and how much you are willing to alter other systems on the truck to make that happen.
If you want the stock components to stay where they are (radiator and a/c condenser) then the solution I suggested is the most effective one I'm aware of and it works. I've not seen a more effective solution leaving stock type radiator and condenser in place. There may be others....I've not seen it or read about or experienced it.
Another thing to check is that if your engine ceterline sits square with the raditor core..ie does the water pump sit square with the radiator core.
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The short of it is his current set up cooled his old 350 (5.7 for you Metric Americans) probably around 250-290 hp 330-340 Ft Lbs peak torque when new, obviously less in the condition it was in when it was replaced.
And it doesn't cool his current 383 (6.2 Liters) with performance cam, the Displacement differ alone is about 9%..
A stock L31 5.7 Vortec is rated around 250 - 255hp 330lbs per torque. The Dyno Sheet on the 383 has 345 peak Horse Power and 416 Ft Lbs of peak Torque - there are a lot of BTUs in the 90-95 Horse power difference of the L31 and the 55-95 HP difference (or more) of his old crate motor. The Horse Power Difference between a stock L31 and the Stroker motor is around a 26% increase. The is a difference in the demand on a cooling system between a Reverse Flow Vortec and a old style Gen I SBC also. With a Reverse Flow engine being less likely to have "Hot Spots" and Steam Pockets in the engine coolant passages.
Elbert's set up May Work, or it May not, Try it to find out - to say otherwise is well you fill in the ________.
And it doesn't cool his current 383 (6.2 Liters) with performance cam, the Displacement differ alone is about 9%..
A stock L31 5.7 Vortec is rated around 250 - 255hp 330lbs per torque. The Dyno Sheet on the 383 has 345 peak Horse Power and 416 Ft Lbs of peak Torque - there are a lot of BTUs in the 90-95 Horse power difference of the L31 and the 55-95 HP difference (or more) of his old crate motor. The Horse Power Difference between a stock L31 and the Stroker motor is around a 26% increase. The is a difference in the demand on a cooling system between a Reverse Flow Vortec and a old style Gen I SBC also. With a Reverse Flow engine being less likely to have "Hot Spots" and Steam Pockets in the engine coolant passages.
Elbert's set up May Work, or it May not, Try it to find out - to say otherwise is well you fill in the ________.
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