V-8 Swap Cooling

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Posting a similar question here as I did over in the 60 section.

Given a V-8 swap into a FJ60 and where a person chooses to run the GM radiator fan and fan clutch. Is it important to fab up the fan shroud such that a portion of the radiator fan blade is exposed to the rear of the fan shroud, and not totally captured within the fan shroud itself?

Currently my fan shroud totally covers the radiator fan blades and I"m having problems with seeing some high temps (just installed this setup about two weeks ago). Saw 220F on the trail Saturday a couple of times.

Looking for comments...anyone experienced this before or have first hand knowledge? I've seen a few posts here and on pirate that mention this...any comments?

I don't want to modify the shroud until I'm sure of this, as my friend put in a lot of work to make this for me and once you cut it...its done.
 
After hitting the other posts you have on this subject the other thing that comes to mind is you may benefit from a larger radiator. Does the temp climb at speed at all? There are folks that have references to say that if the fan blades stick out of the shroud you will get more flow. If you get enough flow I don't know. It does seem that if it makes that much difference you are skirting the edge of "just enough" cooling capacity. With a 7 blade mechanical on a clutch it pulls a massive amount of air. I can't imagine that an extra 1" of shroud would totally kill the air flow (could though).

Is the radiator clean, maybe there is crud in the fins inside or out?
 
After hitting the other posts you have on this subject the other thing that comes to mind is you may benefit from a larger radiator. Does the temp climb at speed at all? There are folks that have references to say that if the fan blades stick out of the shroud you will get more flow. If you get enough flow I don't know. It does seem that if it makes that much difference you are skirting the edge of "just enough" cooling capacity. With a 7 blade mechanical on a clutch it pulls a massive amount of air. I can't imagine that an extra 1" of shroud would totally kill the air flow (could though).

Is the radiator clean, maybe there is crud in the fins inside or out?

Radiator is a 4 core brass type...aftermarket replacment type...its in good shape. The only "larger" radiator that you can use without modification is somethign like the Ron Davis version which I have...(but removed due to leaking). So yeah I would potentially go back with the ron davis radiator once fixed but that's about your only option without seriouis modificaiton. this is a serious fan...soemthing like 9 blades or so.
 
Fan spacing relative to shroud - JeepsUnlimited.com Forums

google search "fan relative to shroud"

I know having it mostly IN the shroud isn't correct...sounds like a shorter fan spacer is in order, or a thinner shroud.

Thanks..I did not think to search around on google or either way appreciate the link. I'm going to trim up the shroud while still on teh truck for right now... maybe shoot for half in / half out ...fan blade vs. shroud. Later on I'll have to remove the radiator to get the shroud off. Its not a great way to do this but you just don't have much room to play with and the battery boxes and water necks get in the way of every ting.

I think later this fall I may devote some time to cutting shroud in half and getting welder friend to weld up some small 90 degree little brackets to join the halfs...that way later on I can just remove teh top half (hopefully) to service the water pump or whatever.

Got the powered tin snips....hope I don't screw it up.
 
Well I did my best (ran out of daylight)...to execute a classic "red-neck" fly by the seat of my pants mod to the shroud. So I was able to do a rough cut on the shroud without having to remove it. But I will have to take it off later on to make a smooth even cut.

No luck this date....about the time I get fired up to test ride it...#$%^ starting running crazy rich. Don't think there is any coonection to my work this date, Last time this happend it was a map sensor. Right now I susecpt (leaking fuel injector, 02 sensor or coolant sensor)...its not showing any codes though which is aggrivating. I'll get my buddy from the local GM shop to check it out.

When I say rich I mean rich...raw gas out the tail pipe. I know whoever came up with the "fuel injection sypder design" for the 5.7 vortec...needs some help. I have the new version of the spyder on my truck and it still is a crap design..(but I guess the new version is the best they can do with what they have.
 
i'm still having a hard time understanding why you don't just get the ron davis radiator fixed? A ron davis radiator is like the king of radiators, and wasn't your setup working before you took it off?
 
Maybe not expressed here but I dont' want electric fans as the primary cooling soure. 2nd I had other radiator ready to go. 3rd If I get the ron davis radiator fixed I want to change the size of the top water neck to match the V-8 radiator hose, and the bottom water neck on the radiator needs to be modified.

At this point I don't knnow why the Ron Davis radiator is leaking....not really happy about that after paying big $$ for it and there are no signs of impact damage.

Where I live you simply don't have a source to repair aluminium radiators aross town.

Yes the combination I had worked, but as I've exprssed...not wanting to do the electric fans any more.

I don't think anyone is going to be thrilled to see their nice expensive radiator leaking for no apparent reason. Right now I don't have a source nearby who can repari the thing.
 
couple of ideas...have you tried pressure washing out the fins on the radiator that is in the rig? take it out put on the ground, hit it with simple green and water. You might be shocked how much dirt comes out.

second check out speedway motors they have great quality aluminum radiators for a inexpensive price.

good luck!
 
The radiator is clean and I do clean it after trips in the mud.
 
Damn Elbert...
Im sorry to hear this because Im doing a 5.3 in my rig right now...
Didnt Iaintscared do your swap?
What harness did you/ he use? Im concerned with the "rich" run issue that youre having. You would think that if youre running the factory harness and computer that these type of issues would be rare at BEST.
As far as the shroud issue...Ive been doing some reading of the shroud designs as well (havent built mine yet) and it seems that the blades half in and half out is the way to do it. I opted for an over sized Al, Griffen radiator as well. One thing I DO NOT want is high engine temps while wheeling.
Is your fan centered in the radiator? Seems like a dumb question, but....never know. I know if I kept my rad. in the stock location it WOULD NOT be centered in the radiator and would have an impact on the cooling.

Good luck and post up what you find.

Keith
 
i'm still having a hard time understanding why you don't just get the ron davis radiator fixed? A ron davis radiator is like the king of radiators, and wasn't your setup working before you took it off?

I know that there are a lot of folks out there that have had great success with Ron Davis. However there have been several instances of the Ron Davis radiator design for 60/62s cracking. Happened to me and it was the second really poor customer service experience that I had with Ron Davis (although they built me a stock replacement they basically told me that the cracking was my fault for installing it like a stock unit using stock mounting). I had mine repaired and it promptly cracked again. After that I ditched it. Use one of these on a 60/62 at your own risk.
 
Elbert.. for what is worth.. my mucho $$$ from AA develop a leak after two years of use.. I however had to option to take it to a local shop and had it fixed....... and I mounted mine with rubber washers on both sides of the fin..

Hope your solve the overheating issue soon..
 
The hottest part of a SB is between 6-8... I ran a return line out of the head between 6-8 back to the radiator for a high performance shower set up I built. It sucked so much heat out of the motor I needed to put a shut valve on it to get heat out of the inside heater. I have never had any engine heat problem but with the return line it could idle forever with AC in the peak of the hottest day in AZ making impossible to overheat. Something to possible consider.
 
Slight hijack, what heads, or does it matter? Just drilled an tapped with a pipe fitting? How does that effect water flow for the rest of the block?
 
Damn Elbert...
Im sorry to hear this because Im doing a 5.3 in my rig right now...
Didnt Iaintscared do your swap?
What harness did you/ he use? Im concerned with the "rich" run issue that youre having. You would think that if youre running the factory harness and computer that these type of issues would be rare at BEST.
As far as the shroud issue...Ive been doing some reading of the shroud designs as well (havent built mine yet) and it seems that the blades half in and half out is the way to do it. I opted for an over sized Al, Griffen radiator as well. One thing I DO NOT want is high engine temps while wheeling.
Is your fan centered in the radiator? Seems like a dumb question, but....never know. I know if I kept my rad. in the stock location it WOULD NOT be centered in the radiator and would have an impact on the cooling.

Good luck and post up what you find.

Keith


Hey,

No aintscared did not do my swap. But I asked him a lot of questions and he offered his advice on things.. Which was a great help to me, he also posted up to my engine swap thread and he is a great resource.

I used the painless wiring harness for my engine. As I stated before I think the harness is well made. What I was not happy to learn was that only certain PCM work with the harness and the 1999 year model PCM was not one of them. I thought painless did a very poor job of letting that be known..both when I bought my harness and after the fact (after I personally called them to ask about it, and I sent a couple of emails)...may have altered their product literatur by now. I don't know. I would probally go with someone like Howell next time around for the harness.

I don't know the issue with the "rich run" . Not sure it is a problem with the harness. One time it was the map sensor out of range...this time I don't know..hope to find out tomorrow. I'm concnered about it not setting a trouble code. I know that the sensor has to be out of range to set the code or other variable apply, but when its spitting gas out the tailpipe I think I should have a trouble code set. (I"m looking in to that) I have an idea, but want to explore some more. I'm runnign the painless harness and OEM PCM...but the OEM PCM has to be programmed to do one of these engine swaps...unless you took everything from teh GM engine and every sensor and moved that to your LC, to include the transmission etc...

Yes...my engine is roughly centered and the fan is roughly centered in the radiator. (previously it was not) When I swapped to clutch driven fan we tradded out the modified advance engine mounts for new ones and centered up the engine. Radiator is in stock location.

Well I have modifed the fan shroud a little on teh top with a powered shear...looks like crap right now, I'll fix later. But roughly the idea is to go somewhere around 50 vs. 50 fan blade exposed / concealed by shroud.
 
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Elbert.. for what is worth.. my mucho $$$ from AA develop a leak after two years of use.. I however had to option to take it to a local shop and had it fixed....... and I mounted mine with rubber washers on both sides of the fin..

Hope your solve the overheating issue soon..

Yeah..I used rubber insulators... and follwed the instructions, even had special ground wire just for the radiator.

If I do get it fixed I'll have the water necks modfied too. Mine is leaking at the bottom tank...drivers side (where the core meets the tank). There may be a shop in Hunstsville that can do what I want? Yeah the RD radiator is crazy expensive...it should explicit mount instructions and come with additional isnulators or whatever....if they feel it can't mount in the strock location (of course I don't recall seeing this in the literature that came with the radiator, or on the MAF web site).

FYI... I ran a be-cool radiator in my 91K1500 for 3yrs and then sold it...its still going fine and its in the stock mounts.

The problem I have is that you can't claim your product is a V-8 swap solution, and that it mounts in the stock location and then claim that when the product was used as designed...that it was mounted wrong. I'm thinking that I paid too much $$ for that.

I will say that I thought the RD radiator was well built and from what I saw I thought the quality was good, and I need to be clear in that I don't knwo what casued the leak..but I"m sure its cracked somewhere and there is no external damage to explain that.
 
The hottest part of a SB is between 6-8... I ran a return line out of the head between 6-8 back to the radiator for a high performance shower set up I built. It sucked so much heat out of the motor I needed to put a shut valve on it to get heat out of the inside heater. I have never had any engine heat problem but with the return line it could idle forever with AC in the peak of the hottest day in AZ making impossible to overheat. Something to possible consider.

Are you talking about the threaded hole in the passenger side cylinder head? You have some kind of plumbing setup on that? THe same location where the temp sender goes on the driver sdie head?
 
Are you talking about the threaded hole in the passenger side cylinder head? You have some kind of plumbing setup on that? THe same location where the temp sender goes on the driver sdie head?

Yes, Yes, and Yes

It works on the same principal as a swirl pot
 
Hey,

No aintscared did not do my swap. But I asked him a lot of questions and he offered his advice on things.. Which was a great help to me, he also posted up to my engine swap thread and he is a great resource.

.

Sorry man.
I remember your build thread in the 60 section, and I thought that it was another RT build. He did most of the swap threads on there, as you know. My mistake.:o
I went with the howell harness and ECM. Ill be looking forward to hearing what is causing the rich burn issue in case I encounter that at some point.
 

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