Long time no post....truck has been on the back burner lately. Having gone through 6 starters, plus a newly developed tapping noise at low RPM/wide throttle (accelerating under heavy load) I've decided to pull the drivetrain so I can make sure the flywheel is installed properly/replace ring gear. I have a bad oil pan leak, possibly a rear main seal leak so I'm going to pull the oil pan and check/clean the oil pickup. I went to drain the oil last night and only about 1.5 quarts came out. I am thinking the tapping noise was due to low oil.


While I'm working on the engine, I am going to look into having a machine shop fill/retap the starter mounting hole that was stripped when I bought the truck (I helicoiled it, but accidentally put the wrong size in, so every starter I install needs to have the bottom hole drilled larger to accept the larger bolt) I am also going to helicoil the two transmission mount holes that were stripped when I bought it.


So here is my question: While I have the engine out and on a stand, what other work should I consider doing? The heads are rebuilt, new valvetrain, new exhaust manifold installed, I have an edelbrock performer intake manifold...trying to avoid removing the top end, but not completely against doing so. Water pump/timing set seems like an obvious choice. Would it be a waste to go ahead with bearings while I have the oil pan off? Would it be a waste to re-ring without having machine work done to the cylinders? Any and all advice is appreciated, as always!

 

The answer to the condition of a shortblock lies in disassembly and micrometers.

Can't be answered on an internet post.

I do recommend that you take NO shortcuts on an honest assessment and approach to the task at hand.

Do it right or don't do it.

 

Thanks for the reply. I understand that engine wear is measured in microns, and simply pulling the oil pan won't tell me much if anything about the condition of the engine. But that's not what I was necessarily asking. Conventional wisdom says if you are going to replace the timing chain, go ahead and spend the couple extra bucks on a water pump since you already took the time to get to it. My question is: what other parts would I be wise to replace (regardless of condition) now that I have the engine out and on a stand? Parts are relatively cheap, labor is the limiting factor. Since I've already done the labor, I'd like to replace what I can (within reason/budget). I'm not interested in rebuilding the engine - it doesn't burn oil and has decent compression across all cylinders. Just wanna make sure I don't have to pull the engine again down the road for a part that could have been replaced this time around. Make sense?

 

Use the good silicon rubber steel reinforced oil pan and valve cover gaskets. Won't leak, reusable, and you don't have to mess with sealant.

 

Thanks F100, great advice. I had been using a rubber gasket for the valve covers, but was surprised to see they leaked from the very beginning. Gaskets are definitely a part where you get what you pay for. Head gasket, intake gasket, thermostat gaskets....all were replaced with the highest quality possible. I have been pleased.

 

Both crank seals, oil pump, timing set, water pump,oil pan gasket...while you have the pan off, pull each rod/main cap and inspect bearings. If they are worn, replace 'em. Dont pull pistons out if it has good compression...and do 1 at a time that way caps dont get mixed up.

 

IMO that is probably the worst thing you could do to a functioning motor, again if the motor has good oil pressure leave it alone.

 

Lance, after tearing the engine down, my list is looking pretty similar to yours. Conanski, would it hurt to at least check the bearings to get an idea of wear? Do you think it's a bad idea because the wear on the bearings is matched to the crank in a way that is similar to lifters being matched to lobes on a camshaft (specific wear pattern unique to each lifter)?


This whole project came about because my starter and flywheel were not happy with one-another. Last night I pulled the flywheel and discovered that all 6 holes are tapped the same. I thought one hole was supposed to be different??

 

FWIW, the aftermarket oil gauge that came with the truck had pieces of the illumination ring broken and laying on the needle, so sometimes it moved, sometimes it got stuck....not real confident whether or not the pressure is good.

 

I think they're all tapped the same (so all six bolts are the same). But the spacing is supposed to be slightly different so the holes only line up one way.

 

Checking them is pretty low risk but if you find 1 or more that is bad a rebuild is the only real way to fix it and have a reliable motor. Yes these bearings take on a wear pattern specific to their location and the forces that act on them, the rod ends in particular tend to go egg shaped over time and the bearings take on a complimentary wear pattern and swapping in new bearing can cause pinch points which can then lead to a premature failure. The crank bearings don't suffer from this as much.

 

That's what I suspected. I pulled the rear main last night and the bearing was very smooth with no grooves that I could feel. The incorrectly installed rear main seal is another indication that this engine has been rebuilt before.


As far as getting the top half of the rear main seal out, do I need to loosen all of the crank caps to provide some wiggle room? It's pretty tight and there is nothing really to grab since the seal was installed flush with the block.

 

Should be able to use the new seal half and gently push it around the journal into the groove. And it should push the old one out during the process. I know chevs can be done that way not positive about sbf.

Oh and offsetting the seal halves from the block and cap slightly has been said to help prevent leaks

 

In all honesty, when you tear down an engine to "OVERHAUL", with no machine work done, it's no different when you replace the rod bearings as it is in this situation. Yes the bores of the small end can become oval shaped, BUT that does not mean the crank journal is oval. If it were, it would have a hard time rotating in the rod bore.
If you want to have a "freshened up" engine, tear it completely down, take to machine shop, have it hot tanked, new cam bearings, honed, crank polished/mic'd, order a re ring kit with main bearings and dont look back. It will last a very long time. If you are worried about the rod bores, get them resized. Will last for YEARS.
I use to work in a machine shop(for many years) and have done this for customers on several occasions.
I dont want to create wave with Conanski as he is a WEALTH of info and help. Just stating my experiences. Good Luck!

 

Well, I had a couple beers Saturday night and decided to go full retard on this engine. The bare block is at the machine shop. Do it right, or not at all....






A few of the main journals had scratches I could feel with my fingernail and the lifters looked pretty tired.


All of this because I was having starter issues....!