Vae Victus
Posting more than I know
Yea, you should junk that thing and put in a 2F. 
Sorry - couldn't resist.
Sorry - couldn't resist.
Builds The Clustertruck Rides Again - Refurbishing a 1975 Chevota
- Thread starter RWBeringer4x4
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I run an SBC400 with a Quad. I bought a reman carb from Jegs, then had a carb guru set it up for me. Runs like a scalded dog! Especially after installing an HEI distributor. Would I live to have a 40 with a 2F? Yes. I won't give up my SBC though. I love the power, sound, and availability of parts too much!
283s issue is they just have too small of a bore to put decent heads on them. The long stroke, small bore is such a torquey motor, though, that I bet it's pretty good. That said, I'd pull a Vortec out of a 97-99 Chevrolet truck/tahoe, rebuild it without a new cam (be in it maybe $300 including purchase price) and run it with efi. It's a best of all worlds - an LS doesn't bolt in place, but the last gen of the sbc really was the right engine. excellent torque, excellent dependability, good fuel economy, dirt cheap to build and parts can be purchased at your local 7-11 (okay, maybe the last is almost an exaggeration).
were I to stay Toyota (not my flavor, but it's an option)... I'd do something in a 2JZ motor but without any turbos.... or a diesel. on my build, it's still possible that I'll use the 6.5 diesel I have rather then the gas motor (the $300 tahoe motor)...
- Thread starter
- #744
To be honest - I don't really care all that much about power - I'd be just as happy with a 135 horsepower 2F. It's the parts availability of the SBC, plus the fact that I have all the conversion pieces to do the SBC conversion (correctly) that I'm sticking to the small block.
Yeah - this would be my second choice. Given that this is my first "project" vehicle I'm somewhat hellbent on keeping things as "analog" as possible and not muddying the water with computer programming. That said, if I pull the 283 and find it to be a lost cause, I might go vortec shopping. My understanding is that the bottom ends of the later Chevy engines are pretty well indestructible.
- Thread starter
- #745
@SuperBuickGuy - since I have your attention in this thread - my water/oil pumps both appear to work 100% on this engine. However, they're tough to get to installed...is this one of those times where I should just throw in a new water/oil pump "while I'm in there" so that they're a known entity down the road, or are they reliable enough parts that I can just keep running them?
tough call on the water pump, if it's working fine - they're not that hard to replace (other then you lose some fluid); however, I've had some crap chinesium pumps lately that failed out of the box...
The LS bottom ends are indestructable, Gen 1 - they can be made pretty stout, but they'll never be a strong as the LS motor. With that said, I've run 750 hp on a stock, 4-bolt-main bottom end without a problem. Nowadays, efi, especially GM ones have such a aftermarket following that to swap in is a plug and play operation and will run with 3 wires hooked up (power, switch power, and ground).
The LS bottom ends are indestructable, Gen 1 - they can be made pretty stout, but they'll never be a strong as the LS motor. With that said, I've run 750 hp on a stock, 4-bolt-main bottom end without a problem. Nowadays, efi, especially GM ones have such a aftermarket following that to swap in is a plug and play operation and will run with 3 wires hooked up (power, switch power, and ground).
- Thread starter
- #747
Yeah - "new" parts really mean nothing anymore. I feel like I buy everything twice. Maybe I'll stick to what I have, since it's working. My main concern is the oil pump - it works fine but dropping the oil pan is a pain in the FJ40 because the axle winds up so close
my tip for oil pans is use the old-style gaskets with just a dollop of silicone in each corner. I've used the one-piece retrofits and think they all suck... sorry for my language, but where I can easily get them not to leak with the cork and rubber gasket; I've yet to be successful with the one-piece. Worse is you have to buy longer studs/bolts...
that said, pulling a couple bolts on the front and one end of each shock would make that job a lot easier... to the point that the time it took to take it apart would be less than struggling with it (a lesson that I took a long time to learn).
that said, pulling a couple bolts on the front and one end of each shock would make that job a lot easier... to the point that the time it took to take it apart would be less than struggling with it (a lesson that I took a long time to learn).
- Thread starter
- #749
Funny you should mention the one-piece oil pan gaskets. I've seen two very different schools of thought on them.
Yours - "they suck."
And yet others swear by them.
From my reading you just have to get the proper thickness gasket at the front (apparently there are two types).
Haven't heard of anyone having to change out the studs to get them to fit...
I've sworn at plenty of them.... if you want to try them, tell me which one you've got - I've several brand new ones that I'll never use... that said, no cussing at me when it leaks.
- Thread starter
- #751
Ok finally caved and ordered a leakdown tester for the engine.
I'm getting very mixed messages from this engine and this should help me get to the bottom of it:
The good: really solid compression numbers from the compression tester - 139-150 psi across all cylinders
no smoke at idle
The bad: Oil fouled spark plugs
blue smoke (oil) when engine is revved up
oil vapor out the breathers (but again, no PCV, so I may have too much crank case pressure)
Leakdown tester should be able to identify whether or not the oil leaking into my cylinders is actually CAUSING the good compression numbers (false positive).
If the leakdown test checks out then I will assume the 283 needs valve seals, deem it fit for service, and order up the SMI carb to (hopefully) deal with my fuel delivery issues once and for all.
Then, it will unfortunately be a hard stop until around April when I've assembled the parts to pull the engine and get busy.
I'm getting very mixed messages from this engine and this should help me get to the bottom of it:
The good: really solid compression numbers from the compression tester - 139-150 psi across all cylinders
no smoke at idle
The bad: Oil fouled spark plugs
blue smoke (oil) when engine is revved up
oil vapor out the breathers (but again, no PCV, so I may have too much crank case pressure)
Leakdown tester should be able to identify whether or not the oil leaking into my cylinders is actually CAUSING the good compression numbers (false positive).
If the leakdown test checks out then I will assume the 283 needs valve seals, deem it fit for service, and order up the SMI carb to (hopefully) deal with my fuel delivery issues once and for all.
Then, it will unfortunately be a hard stop until around April when I've assembled the parts to pull the engine and get busy.
- Thread starter
- #752
Going to copy and paste from another thread over to this one and see if I can get @SuperBuickGuy attention -
I ran a leakdown test on the 283 tonight. My understanding is that this is the "end-all, be-all" of engine health diagnostics. The results, as usual, were sort of mediocre/inconclusive, so I'd like to get some more educated opinions...
A few points, before I get into the details:
1. This was done COLD. I know you're supposed to warm up the engine before you do it, as this will cause the metal to expand and seal better.
2. I did have to rotate the engine BACKWARD a couple times since I passed TDC and went to the instake stroke. I've read in a few places this can unseat a ring slightly and potentially give a false negative read too.
In short - I'm not sure if this is a truly "valid" test but it gets me in the ballpark... Leakage gauge reading and percentage below. All cylinders were fed 90 PSI of air. I found TDC using a vacuum gauge for each cylinder, and worked in the firing order.
LEAKAGE TEST
Cylinder 1: 82 PSI - 9%
Cylinder 8: 78 PSI - 13%
Cylinder 4: 77 PSI - 14%
Cylinder 3: 78 PSI - 13%
Cylinder 6: 74 PSI - 17.8%
Cylinder 5: 68 PSI - 23.33%
Cylinder 7: 73 PSI - 19%
Cylinder 2: 76 PSI - 15%
In short, not IDEAL by any means - just curious as to how bad this is...My understanding is some folks DEMAND the engine be within 1-5% (mostly race engines), lots of places spec 10% as the max acceptable leakage...but I see just as many guys saying that even the GM spec is 25% or better is considered "OK." In which case - the above might not be so awful...
In all cases - leakage came from the valve cover breather holes and oil dipstick - never showed up in the coolant, out the carb, or from the exhaust. So this indicates all leakage through the rings, correct?
As a refresher, here are the compression test results, which all looked pretty great:
COMPRESSION TEST
Cylinder 1: 145 PSI
Cylinder 8: 150 PSI
Cylinder 4: 150 PSI
Cylinder 3: 147 PSI
Cylinder 6: 143 PSI
Cylinder 5: 147 PSI
Cylinder 7: 139 PSI
Cylinder 2: 145 PSI
Another thing that was odd - ocasionally, I would get a VERY low number on the leakage gauge (ie 30%) then I would suddenly hear something "pop" and the cylinder would seal up. Is this a valve sticking, or the ring? Something else entirely?
I ran a leakdown test on the 283 tonight. My understanding is that this is the "end-all, be-all" of engine health diagnostics. The results, as usual, were sort of mediocre/inconclusive, so I'd like to get some more educated opinions...
A few points, before I get into the details:
1. This was done COLD. I know you're supposed to warm up the engine before you do it, as this will cause the metal to expand and seal better.
2. I did have to rotate the engine BACKWARD a couple times since I passed TDC and went to the instake stroke. I've read in a few places this can unseat a ring slightly and potentially give a false negative read too.
In short - I'm not sure if this is a truly "valid" test but it gets me in the ballpark... Leakage gauge reading and percentage below. All cylinders were fed 90 PSI of air. I found TDC using a vacuum gauge for each cylinder, and worked in the firing order.
LEAKAGE TEST
Cylinder 1: 82 PSI - 9%
Cylinder 8: 78 PSI - 13%
Cylinder 4: 77 PSI - 14%
Cylinder 3: 78 PSI - 13%
Cylinder 6: 74 PSI - 17.8%
Cylinder 5: 68 PSI - 23.33%
Cylinder 7: 73 PSI - 19%
Cylinder 2: 76 PSI - 15%
In short, not IDEAL by any means - just curious as to how bad this is...My understanding is some folks DEMAND the engine be within 1-5% (mostly race engines), lots of places spec 10% as the max acceptable leakage...but I see just as many guys saying that even the GM spec is 25% or better is considered "OK." In which case - the above might not be so awful...
In all cases - leakage came from the valve cover breather holes and oil dipstick - never showed up in the coolant, out the carb, or from the exhaust. So this indicates all leakage through the rings, correct?
As a refresher, here are the compression test results, which all looked pretty great:
COMPRESSION TEST
Cylinder 1: 145 PSI
Cylinder 8: 150 PSI
Cylinder 4: 150 PSI
Cylinder 3: 147 PSI
Cylinder 6: 143 PSI
Cylinder 5: 147 PSI
Cylinder 7: 139 PSI
Cylinder 2: 145 PSI
Another thing that was odd - ocasionally, I would get a VERY low number on the leakage gauge (ie 30%) then I would suddenly hear something "pop" and the cylinder would seal up. Is this a valve sticking, or the ring? Something else entirely?
I so rarely do a leak-down test. To me a leak down test is the way to tell me whether or not the head is leaking or the rings. When you pressurized the cylinder, did you hear air escape from the block or the intake on the >10% cylinders? I also don't do the test with the piston at TDC, I do it from BDC because cylinders, as they wear, tend to lose more metal at the bottom then at the top.
Do you still have the spark plugs? I'd be interested to see what you saw with them.
But as a general rule, I rebuild motors that have wildly dissimilar compression readings. That one doesn't hit it - it sounds to me like you may have leaking oil seals and/or a burned valve or two. The 283 was never a motor designed to run on unleaded fuel, so unless the heads have been rebuilt (and a very expensive rebuild it is), odds are it doesn't have bronze guides or hardened seats. That causes problems in a couple ways - 1) the lead protected the valve stem from wear - so without any kind of lubricant, the stem will wear; and 2) the lead cushioned the valve when it landed - especially on the hotter exhaust port. That means that it will overheat the valve which will cause it to warp slightly and become what we refer to as a burned valve - burned valves don't seal well, and the hotter they are the less they seal. Which brings us to the test at cold... it may not have told you much at all (other then the direction the air is leaking from).
Do you still have the spark plugs? I'd be interested to see what you saw with them.
But as a general rule, I rebuild motors that have wildly dissimilar compression readings. That one doesn't hit it - it sounds to me like you may have leaking oil seals and/or a burned valve or two. The 283 was never a motor designed to run on unleaded fuel, so unless the heads have been rebuilt (and a very expensive rebuild it is), odds are it doesn't have bronze guides or hardened seats. That causes problems in a couple ways - 1) the lead protected the valve stem from wear - so without any kind of lubricant, the stem will wear; and 2) the lead cushioned the valve when it landed - especially on the hotter exhaust port. That means that it will overheat the valve which will cause it to warp slightly and become what we refer to as a burned valve - burned valves don't seal well, and the hotter they are the less they seal. Which brings us to the test at cold... it may not have told you much at all (other then the direction the air is leaking from).
- Thread starter
- #754
What makes a 283 head so much more expensive than a 350 to rebuild?
As for the leak down test - it was all done cold with the cylinders at TDC. All leakage I could detect was past the rings and out the valve cover breathers and oil dipstick. Nothing appreciable from the exhaust or carburetor. Nothing in the coolant.
The spark plugs are black, with a little oil, but mostly carbon. (less than about 3 hours of run time on them) but I have been fooling around with fuel mixtures and timing so much I'm not 100% shocked.
I do think my valve seals leak - or possibly worn valve guides as you mentioned.
I don't think valves themselves are leaking (air) though.
If you are thinking about pumping any $ into the 283, check this out:
http://www.summitracing.com/parts/nal-10067353/overview/
And it comes with a 12 month warranty
http://www.summitracing.com/parts/nal-10067353/overview/
And it comes with a 12 month warranty
a bit of oil isn't really anything to worry about on an older motor. Keep in mind, those motors have a crankcase vent system that vents to the road through a sizeable tube. My concern would start at built-up carbon, or smoke-screens.
why it costs so much to rebuild? volume, everyone does 350s (even me). As there is no substitute for cubic inches 350 > 283, that means the 350 gets the love and the 283 doesn't. That said I've spent crate-LS7 money building (not yet done, mind you) a twin turbo 455 Buick - but it's for a special car and special project.... which is kind of entertaining to me because many times the smaller motor is a better option for whatever is being built.
why it costs so much to rebuild? volume, everyone does 350s (even me). As there is no substitute for cubic inches 350 > 283, that means the 350 gets the love and the 283 doesn't. That said I've spent crate-LS7 money building (not yet done, mind you) a twin turbo 455 Buick - but it's for a special car and special project.... which is kind of entertaining to me because many times the smaller motor is a better option for whatever is being built.
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- #757
I've seen this, and it is very tempting...The issue is I would need an intake, exhaust, pulleys, harmonic balancer, flywheel......not to mention all the brackets, etc. to mount up the accessories. Even if I transferred as much as I could over from the 283 (HEI dizzy, intake, etc.) It would still be up over $2000 when all is said and done. Now, I understand that for a brand new engine, that is chump change, but the fact remains, if the 283 is serviceable, I can get it resealed and back in the truck for a lot less.
That said, the 283 needs a balancer, exhaust, and probably pulleys as well...
As for the cost breakdown - I think I could get the 283 new seals, new balancer, exhaust manifolds, and pulleys for about $400. Of course, when I add on the "nice to have's" like shiny valve covers, oil/water pumps "while I'm in there" etc. It quickly goes to about $800.
That said, it's still about 1/2 the cost of the new 350...And it this 283 is relatively healthy, I'd rather save the extra money for other projects.
Yes and no - Mine is a very late 283 (circa 1965) so it has a lot of the features of the early 350's and 327's. There is no vent tube, it has a spin-on oil filter, etc. In fact, in my (even) younger and (even) dumber days when I bought this truck, it was sold to me as a 350. Now that I understand the nuances, it's totally obvious...
For me, I don't particularly want/need/care about POWER, I just also don't want to spend $400 - $800 refreshing an engine that's well on its way to the junkyard...
Now, if this engine will run another 5 years with 15-20% leakage and good compression - I'll probably just run it. If 20% leakage is going to be 30% leakage in another 1000 miles...that's another story entirely.
- Thread starter
- #758
@SuperBuickGuy - So given that my leak-down wasn't catastrophic, I'm not getting a TON of smoke out the tailpipe, and my compression numbers are good - if you were me (on a budget), would you refurb this engine and run it (without a full re-ring, pistons, etc.)? Or am I throwing good money after bad?
As for carbon buildup - Wouldn't a can of seafoam through the intake take care of this pretty well?
I'd run it until it died or became so smokey that the cops stop you and give you pollution tickets.
To "fix" the oil leak issue, I'd use a hotter plug so you don't have to change it as often (has a tip that reaches further into the cylinder and won't foul as quickly)
As for accessories - you can bolt everything but the harmonic balancer from your 283 to a 350. I presume, of course, that the 350 is of the two-piece design - otherwise you'll have to get a new flywheel as well. That said, both of those parts are less than $50.00 new.... stock flywheels are $30.00 and stock balancers for a 350 is $16 (and for those prices, I'd never reuse either).
To "fix" the oil leak issue, I'd use a hotter plug so you don't have to change it as often (has a tip that reaches further into the cylinder and won't foul as quickly)
As for accessories - you can bolt everything but the harmonic balancer from your 283 to a 350. I presume, of course, that the 350 is of the two-piece design - otherwise you'll have to get a new flywheel as well. That said, both of those parts are less than $50.00 new.... stock flywheels are $30.00 and stock balancers for a 350 is $16 (and for those prices, I'd never reuse either).
- Thread starter
- #760
When I say oil leaks - I mean the rear main seal, oil pan, intake manifold bolts, etc. that leak all over my garage. The oil in the cylinder is actually pretty minimal - Doesn't cause fouling to the point of causing misfires or anything.
Accessories: It's not so much that I CAN'T transfer them over, it's that I wouldn't want to. Harmonic balancer is shot anyway (wobbles, ring may have shifted). Water pump is of unknown age/condition. Exhaust manifolds are leaking. I'd probably swap over the intake, dizzy, and carb, but everything else would need replaced, along with the proper mounting brackets for power steering pump, alternator, etc. My whole setup is kind of rigged right now due to the lack of head mounting bosses.
The engine has to come out either way - so while it's out, might as well reseal it. I'd probably do the valve seals as well, just to see if that stops the oil in the plugs.
I guess I'll have to do some math and see what I'm looking at for a new crate engine. I don't think I could come anywhere close to the cost of dropping this one back in with minimal overhaul, but we'll see...
