pdrayton

I probably should have checked my main bearings, but I thought you couldn't do that without removing the engine. Maybe it was that you couldn't remove the crankshaft without removing the engine, but maybe the main bearings can be replaced without removing the crank? Let me know if you find out!

you'd might be surprised at how little of an over size bearing will tighten up that space. Surely the bigger green plastigage would give you some reading?

lunghd

Well - finally got all the rod bearings swapped. Green plastigage is smaller than the red & that one front bearing was wwwwwway worn. Spun too.

Front-most rod journal is worn unevenly & when plastigaged w/ a .020 bearing in place it shows areas that indicate I need to go to .030... and other areas that are fine at .020.
Just for fun I put in a .030 bearing and when tightened up I couldn't easily turn the crank anymore. *sigh* Valleys had good clearance but hills didn't. No hardcore ridges but it was definitely worn.
Put it all together with the .020 bearing and the engine is MUCH quieter -but- I can still hear that darn rod faintly at high revs. I didn't bother to check the mains after finding that much slop in the front rod bearing. I found a darn good 'how-to' on changing the main bearings 'in the car' - applies to engines w/ 2-pc rear main seal, though.
Changing crank & rod bearings in the car. - Corvette Forum

After looking underneath... aside from the PITA that it will be to heave a new crank up into place I'm reasonably sure I can swap out the crank with the motor in place after pulling the harmonic balancer & unbolting the torque converter & flex plate. That one piece rear main seal might be a problem, though. Don't have any experience with how that goes in, only old-skool 2 piece mains. I'll start a new thread for that in case someone is searching for 5.7L info.

I appreciate your feedback on your experience. Glad I found this thread.

tinybird

Note to Self; something seems strangely suspicious that a lack of interest or posting on replacing rod bearings. I just replaced all the rod and mains on my 2500 express without much of an ordeal at all.... just sayin, oh by the way did it in my driveway and no engine pulling required... for such a popular van being driven around by a bunch of handy peeps, you would thing that this would be popular. But maybe the forums are for a different purpose all together...

solwav

tinybird


No sure what you are referring, I can not speak for other members but replacing bearings with the engine installed is not how I would proceed. Let me state I have replaced Chevy,Dodge,Ford van engines and several gas motor home engines. When replacing bearings or any internal engine work keeping everything clean is imperative. Now pulling a engine from a Dodge van is easy as you can remove the pass seat and pull the motor through the pass door. Removing engine from Chevys and Fords the bumper, header panel, radiator support etc..... must be removed and I do agree is a bit of work.


After the engine is out you can remove the crank and either hand polish the journals with twine and emery cloth or have it turned at a shop Most important you can give the crank a solvent bath and make sure the bearing surfaces are clean. Two days and a good friend (helper) you could do the job on the engine stand have the van running again and not have to cross you fingers while watching the oil gauge at first start up. Also if there was any other suspect part(s) you can tackle them easy with the engine on a stand.


Again why so few responses I have no answer but if I tried the in the chassis job with my luck I would likely make the oil pressure worse. It is great to know both of you have had success and may you both get many more miles out of those engines.