At a crossroads - Do I open this can of worms? (V8 Location/Clutch Replacement) (1 Viewer)

[Cdaniel]

Yeah it is a confusion now that I read it again. Bottom line is I used that walker pipe number and Dorman manifold on both sides. Pipe is close to a stock pan, but does not touch. Use some quality donuts as the Chinese supplied ones cooked away fast. I recommend gaskets at the head.

 

[RWBeringer4x4]

Ok, all -

After a long detour into my electrical system I'm back to collecting parts for this project. This will be long and nobody will read it, so I'll ask the questions first.

First, my questions - I'm back on the hunt for Ram's Horns. I cannot find a consensus, ANYWHERE as to whether the Dorman 674-501 and 674-502 are 2 inch or 2.5 inch outlets. Some sites say they are 2.0 inches, some say they are 2.5 inches. I have an e-mail into Dorman technical support to (hopefully) get an official answer - but if anyone here knows for sure, I'm listening!

I'm ASSUMING these are a matched set, and ASSUMING they're 2 inches because folks generally use a pair of the -501 manifolds with the Walker Y-pipe 42087, which is 2 inches on both ends.

Unfortunately, I'm going to need to run a heat riser or spacer. Since I have a 283SBC and not a 350, I have no mounting points on the heads for accessories (like the alternator) so it looks like I will actually NEED the alternator mount on the 674-502 manifold.

This is assuming the 283 is worth keeping, which is TBD (but I hope I can).


As for other parts, so far, here is what I have:

Downey Conversion Bellhousing
Low Profile GM Clutch/Pressure Plate
Clutch Fork from Toyota 4-speed
T/O Bearing Hub for Toyota 4-speed
Beating Retainer for Toyota 4-speed (in case mine is toast or modified)
Toyota 4-speed Throw-out Bearing
GM Non-Magnetic Pilot Bushing
Downey Engine/Transmission Mounts
AA Propellar shaft T-case crossmember (re-using mine)
Early FJ60 4-speed top cover
FJ60 shifter (to replace mangled 40-shifter)
Transfercase shift linkage (to replace my dog-legged one)
All transmission seals and gaskets
Clutch fork boot and cover for bellhousing
4X Toyota SQUARE motor mounts



Parts to buy (assuming 283 has good compression/seems salvageable)

Dorman Ram's Horns (674-501 and 674-502)
Manifold Alternator Bracket (mine is cracked and won't survive removal)
Walker Y-Pipe 42087
Heat Riser Spacer - Year One JS015
Manifold Donut Seals
Exhaust Manifold Gaskets
Engine Seals - Oil Pan/Timing Cover/Rear Main Seal (mine all leak)
Fuel Pump (I think mine is leaking into the block)
Thermostat (pretty sure mine is dead)
Thermostat Housing Gasket (mine leaks)

Related Project:

Clutch hard-line to passenger-side
Replace clutch soft line

Jobs I will Most likely shop out:

Welding in the new engine/tranny mounts
Exhaust/Muffler (Y-pipe, back)
Driveshaft Length Modification
Flywheel resurface


I THINK that is most likely everything this project will entail. I'm not planning on doing a full rebuild of the engine, at this point - I just want to do enough to keep it going...Down the road I will probably swap it for something with something that has emissions controls that will allow me to get it through inspection, as opposed to hiding behind a "historic" registration.

 

[RWBeringer4x4]

Ok, just to update this with new information -

I heard back from Dorman technical support. The manifold part numbers listed above, 674-501 and 674-502, are confirmed to be 2-inch dump manifolds. This should have been obvious given that folks use them with the 2-inch Walker Y-pipe, but I figured I would spell it out here. There are a ton of sites/forums out there that have these listed as 2.5 inch dumps.

If anyone IS looking for the 2.5 inch dump manifolds, those are part number 674-503 and 674-504.

 

[shelfboy1]

how long has the bearing been in there ? if you need the truck punch a hole in the metal housing around the bearing and grease it .ive used aa and downey and never had a problem with either one . i like the downey adapter because you can get in their and hose stuff off .or when your a 100 miles from home and your to bearing starts whining you can do the grease thing to get you home .as far as over heating 455s and 501s fill the whole engine bay and they dont overheat ,but it doesnt get over a 100 here good luck

 

[RWBeringer4x4]

how long has the bearing been in there ? if you need the truck punch a hole in the metal housing around the bearing and grease it .ive used aa and downey and never had a problem with either one . i like the downey adapter because you can get in their and hose stuff off .or when your a 100 miles from home and your to bearing starts whining you can do the grease thing to get you home .as far as over heating 455s and 501s fill the whole engine bay and they dont overheat ,but it doesnt get over a 100 here good luck

@shelfboy1 - I have no idea how long the bearing has been in there. It has been "chugging" since I bought it about 3 years/500 miles ago, not sure when it was last replaced by the PO. It was bad when I bought it, and I haven't been able to adjust it out. It doesn't whine yet, it just "clunks." You can hear it over the engine in the video I posted back in the first post.

I don't need the truck, and there's no real way to access it through the Scattershield. How do you get into the downey adapter? Seems like it's a full "ring" like the scatter shield, no removable access plate from underneath like the AA unit (but that should also make it stronger).

I'm not THAT far from you, so the weather is about the same (I'm in North East, MD). I drive through Erie all the time to go fishing/hiking/camping. I'm not going to a big block. Not too worried about cooling (yet). I'm sure if I put the engine where it belongs (and where it has been put by countless other MUD members) I'll be fine. I'll probably replace the radiator while I'm at it, unless this one is salvageable.

 

[RWBeringer4x4]

Ok guys,

It's looking like this is official - Engine is most likely coming out in April, as long as my welder buddy is available. I've spent the last couple months doing some diagnoses on the engine, and I've been pretty happy with what I've found (sort of)

The good: Compression is 139-150 across all cylinders - so a complete swap/rebuild shouldn't be necessary

The bad: It leaks from every orifice - Rear main, timing cover, intake manifold bolts, etc.
Brand new spark plugs are already badly oil fouled. Given the decent compression, this sounds to me like leaking valve seals.
Harmonic balancer may have "shifted" and wobbles on the crankshaft (might be dead) - so I plan to replace it.

The plan is to tear this thing down, and reseal it entirely while it's out of the truck. Anything rubber, paper, or cork, will get replaced.

My questions are:

1. Currently, the water pump and oil pump seem to work fine. The truck has about 15psi at idle, and upwards of 50 when cruising. This drops to about 30 once the oil is hot. Water pump is definitely pushing water, and not leaking. That said, they are somewhat of a pain to get to. Are these parts that I should just replace "while I'm in there," given that I have no idea what their history is?

2. Pulleys - my water pump pulley is dented. Nothing is lined up right. I have a permanent belt squeal at about 3000RPM. I'm considering replacing the crank (2 groove) and water pump pulleys. Do these have to be the same diameter as the harmonic balancer? The balancer currently on my 283 appears to be about 6.75in. The pulley matches. Most of the pulleys I can find are 7 inches. Currently, it looks like my water pump pulley is about 5-5.5in. (smaller than the crank pulley). It also appears that most crank/pump pulley sets are 1:1. Any thoughts/recommendations for this?

 

[toyotaspeed90]

Keep in mind - if oil is leaking into the cylinders (especially through valves, which can happen when the engine is off) then compression numbers can bump up.... Oil around the rings actually increase the seal, making compression higher. You may want to do a leakdown test instead.

When an engine has blown that many seals/gaskets - makes you wonder if there's excessive crank case pressures.

Water pumps are cheap and actually pretty easy (drop the bib down, pull the radiator, pull the belts, loosen/move if needed accessories, swap the pump).... but if it's out, might be something to consider. Oil pressure is dependent more on bearing clearances than the pump itself....

 

[RWBeringer4x4]

Keep in mind - if oil is leaking into the cylinders (especially through valves, which can happen when the engine is off) then compression numbers can bump up.... Oil around the rings actually increase the seal, making compression higher. You may want to do a leakdown test instead.

When an engine has blown that many seals/gaskets - makes you wonder if there's excessive crank case pressures.

Water pumps are cheap and actually pretty easy (drop the bib down, pull the radiator, pull the belts, loosen/move if needed accessories, swap the pump).... but if it's out, might be something to consider. Oil pressure is dependent more on bearing clearances than the pump itself....

Yeah, I have given a leak down test some consideration. I don't have a leak-down test kit, however, so it's not really an option without buying one, or paying someone to do it. I usually let the engine warm up to full operating temperature before I pull the plugs - which hopefully clears most of the oil out of the cylinder. Definitely not a perfect solution, but given that I don't get much blue smoke out the tailpipe and the engine doesn't seem low on power, I'm pretty confident that the rings and pistons are probably OK. The blue smoke I DO see out the tailpipe is generally on hard acceleration - nothing at idle, which again leads me to believe it's bad valve seals.

As for blown gaskets and leaks - I very well may have high crank case pressure - there's no PCV valve, just a breather on both valve covers. I do get smoke out the breathers as well, which absolutely points to high crank case pressure as well. The engine also sat for a long time before I got it running, which may very well have dried out most of the seals. I honestly have no idea how long they've been on the engine. Plus, it's a small block chevy - they pretty much leaked from the factory...It has always leaked from the rear main seal, the (worse) leak from the front of the oil pan or the timing cover (can't tell) starter just last year after the truck sat for a few months while I rebuilt the axles and converted to discs.

The engine will be getting a new carb/PCV setup as part of the repairs which will hopefully help preserve the replacement seals.

 

[handcannon]

About the oil pressure-- I've read/heard that worn cam bearings can be the biggest culprit when looking for the cause of low oil pressure. I'm not an expert on this subject so this is just hear-say type of information. But check out what the oil pressure specs are for your motor, and check out my hear-say info to see if it is actually true.

Don

 

[RWBeringer4x4]

About the oil pressure-- I've read/heard that worn cam bearings can be the biggest culprit when looking for the cause of low oil pressure. I'm not an expert on this subject so this is just hear-say type of information. But check out what the oil pressure specs are for your motor, and check out my hear-say info to see if it is actually true.

Don

I don't think I have an oil pressure issue. At idle, with a warm engine, it sees about 12-15lbs of pressure, driving it sees 25-30lbs. Cold, when the oil is more viscous, it sees closer to 50lbs under load - so oil pressure seems just about exactly where it should be.

What I'm really asking is, since I'm going to have the oil pan off, and the engine out of the truck, is it stupid to not just pony up for a new oil pump and water pump while they're easy to get to? Neither one of them currently exhibits any issue, so I'd basically be pulling out good, working parts. Just not sure if they're enough of a "high failure rate" item to make it worthwhile.

I'm basically flipping a coin between the unknown history/lifetime of the parts on my engine vs. the questionable quality of a lot of aftermarket parts/rebuilds these days.

 

[toyotaspeed90]

As for oil pressure - pushrod motors don't have cam caps... those are in overhead cam motors.

Crank main caps and rod caps will absolutely be the determining factor for oil pressure.

Rule of thumb is oil pressure should increase about 10psi per 1000 rpm's... Toyota's have REALLY low idle psi tolerances (as in - low oil pressure on more modern engines is around 3-5psi at idle, even though most of those engines make 10-30psi at idle).


Water pump on an SBC is easy to get to whether the engine is in or out of the vehicle (swapped mine out in about an hour and a half, taking my time, and I have a couple extra coolers in the way). As for the oil pump - you can pull it and see if it's worn, but probably not. Might be a better idea to pull some bearings and take a look at them.

 

[handcannon]

As for oil pressure - pushrod motors don't have cam caps... those are in overhead cam motors.

Crank main caps and rod caps will absolutely be the determining factor for oil pressure.

Rule of thumb is oil pressure should increase about 10psi per 1000 rpm's... Toyota's have REALLY low idle psi tolerances (as in - low oil pressure on more modern engines is around 3-5psi at idle, even though most of those engines make 10-30psi at idle).


Water pump on an SBC is easy to get to whether the engine is in or out of the vehicle (swapped mine out in about an hour and a half, taking my time, and I have a couple extra coolers in the way). As for the oil pump - you can pull it and see if it's worn, but probably not. Might be a better idea to pull some bearings and take a look at them.

I have no real experience with oil pumps, just that they seem to work almost forever. If I was rebuilding a motor I'd replace the oil pump. But, otherwise as long as you have good oil pressure I think I would leave it alone.

toyotaspspeed, I'm not sure that you were referring to my post when you mentioned cam caps. But, just in case you were, I was talking about just the bearings only. Now, I do agree that, in my knowledge, only overhead cam motors have cam caps. But, in order to keep from confusing those who may not have a great deal of knowledge about motors, pushrod motors have what looks like a freeze plug in the block that seals the back end of the cam. There is a big difference in looks and serviceability between cam caps and "freeze plugs".

Rick, on the subject of water pumps, I would have to agree with toyotaspeed, they are usually very easy to access on an SBC for replacement. However, if the cost of a replacement pump is low enough that the frustration factor cost of having to replace a pump when in the vehicle exceeds the cost of the new pump then you may want to change it when the motor is out. That's going to be your call.

Just to clarify why I specified SBC water pumps, I recently helped my son replace a water pump in his Acura (overhead cam motor). That was my first experience changing a water pump on an overhead cam motor. Hopefully that is JUST a Honda Motors design, and not an example of all overhead cam motors. I have never had such a rough time changing a water pump. The water pump is run off the timing belt, and you have to take apart almost all the front of the motor just to access the water pump. It is an interference fit motor, and whenever you replace the timing belt you also replace the water pump, or vice versa, just because of the difficulty of access.

Don

 

[RWBeringer4x4]

As for oil pressure - pushrod motors don't have cam caps... those are in overhead cam motors.

Crank main caps and rod caps will absolutely be the determining factor for oil pressure.

Rule of thumb is oil pressure should increase about 10psi per 1000 rpm's... Toyota's have REALLY low idle psi tolerances (as in - low oil pressure on more modern engines is around 3-5psi at idle, even though most of those engines make 10-30psi at idle).


Water pump on an SBC is easy to get to whether the engine is in or out of the vehicle (swapped mine out in about an hour and a half, taking my time, and I have a couple extra coolers in the way). As for the oil pump - you can pull it and see if it's worn, but probably not. Might be a better idea to pull some bearings and take a look at them.

I have no real experience with oil pumps, just that they seem to work almost forever. If I was rebuilding a motor I'd replace the oil pump. But, otherwise as long as you have good oil pressure I think I would leave it alone.

toyotaspspeed, I'm not sure that you were referring to my post when you mentioned cam caps. But, just in case you were, I was talking about just the bearings only. Now, I do agree that, in my knowledge, only overhead cam motors have cam caps. But, in order to keep from confusing those who may not have a great deal of knowledge about motors, pushrod motors have what looks like a freeze plug in the block that seals the back end of the cam. There is a big difference in looks and serviceability between cam caps and "freeze plugs".

Rick, on the subject of water pumps, I would have to agree with toyotaspeed, they are usually very easy to access on an SBC for replacement. However, if the cost of a replacement pump is low enough that the frustration factor cost of having to replace a pump when in the vehicle exceeds the cost of the new pump then you may want to change it when the motor is out. That's going to be your call.

Just to clarify why I specified SBC water pumps, I recently helped my son replace a water pump in his Acura (overhead cam motor). That was my first experience changing a water pump on an overhead cam motor. Hopefully that is JUST a Honda Motors design, and not an example of all overhead cam motors. I have never had such a rough time changing a water pump. The water pump is run off the timing belt, and you have to take apart almost all the front of the motor just to access the water pump. It is an interference fit motor, and whenever you replace the timing belt you also replace the water pump, or vice versa, just because of the difficulty of access.

Don

Thanks, both of you, for the very detailed input.

I think I may just run them, for now. There are a lot of very big unknowns with this engine - I don't want to dump a TON of money into it. I keep going back and forth as to whether or not I want to swap it. I really can't get a good feeling for whether the rings in this engine are good or not.

To recap:

Positives:
No smoke at idle
idles beautifully, doesn't seem short on power when driving
Great compression (139 - 150 across all cylinders) - but this could be because the cylinder's full of oil...
Good oil pressure (so probably good bearings)

Negatives:
All spark plugs black. 2 or 3 showing oil, the rest might be carbon
Smoke out the valve cover breathers - BUT I have no PCV setup on this engine just passive breathers which could be part of the problem
SOME blue smoke out the tailpipe when the engine is revved when sitting (nothing noted while driving, however)
Only about 15 In. Hg. of vacuum - which, to my understanding is on the low side of acceptable.

Honestly, I think the biggest variable right now is truly the Quadrajet. It's WAY too much carb for the engine (800 CFM Buick). Rebuilt by me (intermediate mechanic at best). It also has a warped air horn, limited choke functionality and, currently, is running way rich and flooding.

I think what I'll do is replace the carburetor with a known, good entity (SMI Chevy Quadrajet, set up for a 283), then run all these tests again.

So many of the "negatives" above could be issues with the carb, not the engine:
Bad vacuum - leaky throttle plates/warped air horn
Fouled plugs - rich mixture

Really, the smoke out the breathers is my biggest concern. There's quite a bit from the driver's side. Granted, with no PCV, SOME is inevitable, but the only way you should be getting smoke from a breather is high crank-case pressure, and the only cause of that is blow by, and the only cause of blow by is worn rings.

So I guess I'll wait the 6-8 weeks for a carburetor, bolt it up, tune everything and run the tests again. I'm guessing a leak-down tester is in my future.

 

[toyotaspeed90]

FYI, a PCV is really just a breather with a small valve - that keeps it closed if there's no pressure built up in the crank case. Constant positive crankcase pressure (when there is a breather or a PCV) can be signs of excessive blowby.

Handcannon - water pump difficulty on OHV/SOHC/DOHC motors depends on engine orientation within the bay and engine design. Similar to how distributor replacement on a 70's SBC is easy and a 95 Z28 Camaro (the ~2 year sting where Chevy put it behind the water pump - where distributor replacement is like an 8 hour job) varies as well.

 

[RWBeringer4x4]

FYI, a PCV is really just a breather with a small valve - that keeps it closed if there's no pressure built up in the crank case. Constant positive crankcase pressure (when there is a breather or a PCV) can be signs of excessive blowby.

Handcannon - water pump difficulty on OHV/SOHC/DOHC motors depends on engine orientation within the bay and engine design. Similar to how distributor replacement on a 70's SBC is easy and a 95 Z28 Camaro (the ~2 year sting where Chevy put it behind the water pump - where distributor replacement is like an 8 hour job) varies as well.

How does one confirm constant positive crankcase pressure, and what's considered "excessive?" Can I stick a vacuum/pressure gauge into the breather hole (sealed in, obviously) and measure crack case pressure or is that a ridiculous concept? It's very possible that I'm getting more smoke out the driver's side breather because that's where I just added oil too - could just be residual burning off or something...Time will tell.

As for hard-to-change water pumps - the worst I've seen was my father-in-law's 51 mercury. Ford Flathead V8's have twin water pumps that also happen to be the car's motor mounts...

 

[toyotaspeed90]

and we've come full circle - you would want to do a leakdown test to check your rings....

 

[RWBeringer4x4]

and we've come full circle - you would want to do a leakdown test to check your rings....

Ok, leak-down tester has been ordered. Hopefully this will put all these questions to rest once and for all. I only have a little 6gal Harbor Freight compressor but hopefully that will get the job done.

 

[RWBeringer4x4]

@toyotaspeed90 & @handcannon and anyone else following along.

Ran the leakdown test tonight - results are in.

Let me preface this by saying the engine was COLD, which I understand will lead to more leakage, because the metal hasn't expanded. That said, here are the results - displayed in firing order:

All cylinders were fed 90 PSI of air. I found TDC using a vacuum gauge for each cylinder, and worked in the firing order. I also had to rotate the engine backward a few times (went past TDC) which I understand can affect the ring seal. 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:

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...

As a refresher, here are the compression test results:

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

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?

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?

 

[shelfboy1]

ive used both adapters for many years downey and aa ,downey gets the nod because of the inspection cover and access to the clutch .having that opening has saved me from getting towed several times

 

[RWBeringer4x4]

ive used both adapters for many years downey and aa ,downey gets the nod because of the inspection cover and access to the clutch .having that opening has saved me from getting towed several times

I already picked up a Downey adapter. That said, it's AA that has the inspection cover. Downey's is a solid piece.