Blazer Forum - Chevy Blazer Forums

Blazer Forum - Chevy Blazer Forums (https://blazerforum.com/forum/)
-   Engine & Transmission (https://blazerforum.com/forum/engine-transmission-35/)
-   -   Rebuild or Put back together?? (https://blazerforum.com/forum/engine-transmission-35/rebuild-put-back-together-52356/)

swartlkk Dec 16, 2010 07:17 PM

Wonder what bent the rod...

Frog Dec 16, 2010 08:32 PM


Originally Posted by swartlkk (Post 387985)
Wonder what bent the rod...

I do not know....all the guy said was that it had a blown head gasket and that was all he said.

The valves look fine. Before I removed the head I was checking the valve action on the head to make sure they were all moving freely and none of them stuck open.

My only guess would be that....it sat over night and when he went to start the engine, the piston was maybe in the middle of the cylinder bore and was probably almost full of water and it started then maybe died due to hydrolock.

Cause if it happened while driving it would be much worse than that IMO.

Just a guess on my part though....really dont know the full history though.

TZFBird Dec 17, 2010 05:32 AM

I would guess the discoloration is because of the piston rocking slightly in the bore which would rub any oxidation off the bores.

If you suspect the rod is bent, why chance it? These motors are a dime a dozen. I was just on Craigslist and there is a guy with boxes of 4.3 parts in his front yard just about giving them away. Didn't see any rods in the pics though.

Frog Dec 19, 2010 09:38 PM

Ok, so I got the engine pulled today and removed the oil pan to check things out.

After I removed the pan, I removed the rod and piston and this is what it looked like.

Sorry just noticed how blurry some of the pics are.

http://i672.photobucket.com/albums/v...r/102_5576.jpg

http://i672.photobucket.com/albums/v...r/102_5576.jpg

Clearly it is bent, not too bad though I have seen worse....then I was inspecting the piston and noticed this.

http://i672.photobucket.com/albums/v...r/102_5582.jpg

Looks like it has been hitting the counter weigh on the crankshaft.....must have been driving with it like this for a little while.

I will get pics of the bearings soon.

But here is the crank shaft.

http://i672.photobucket.com/albums/v...r/102_5577.jpg

http://i672.photobucket.com/albums/v...r/102_5581.jpg

I can hang my fingernail on the scored section on the crank so it will need to be turned. :(

http://i672.photobucket.com/albums/v...r/102_5580.jpg

http://i672.photobucket.com/albums/v...r/102_5578.jpg

This is where the piston skirt was hitting the counter weight.

http://i672.photobucket.com/albums/v...r/102_5583.jpg
Here is the #1 rod bearing.

So, would it be better for me to fix all of this or get an engine with say 70k miles or so and just put that in and drive it???

I am on a fairly tight budget...but, who isn't these days....I can get an engine from intake to oil pan with all accessories for 375.

swartlkk Dec 20, 2010 07:46 AM

The rest of the engine looks good. That bearing doesn't look too awful bad, but you would need to have the crank mic'd to make sure that you wouldn't need to have work done on it. You may be able to clean it up with some fine emery cloth and call it good even though you can catch your finger nail into it. I have seen worse last a VERY long time.

I'd say fix it, but you may want to tally up the costs involved. The thing with a junkyard motor is you have no history. It could have been beaten to within an inch of its life or it could have been pampered and still look brand new inside at 70k miles. If you spend $500 rebuilding your engine properly, you have a 'new' engine for all intents and purposes.

Frog Dec 20, 2010 02:48 PM

Went home at lunch and double checked some things.

Piston is original size @ 3.995"
Rod Journal on crank checks out @ 2.250"

I checked the scoring on the crank and I can feel a slight divot....can't really hang my nail on it....rather I can feel the small groove but it glides right over.

I have found a re-ring kit with, Rod, Main bearings, full gasket set and rings for 125 bucks. Found a rod for 30 and if no machine work and emory cloth will work on the crank then that would be great!!

Should I hone it again even though I can see the cross hatching???

I will mag the block and crank after Christmas...I still need to check the cylinder bore though.

swartlkk Dec 20, 2010 04:01 PM

I would hone the cylinders with a flexible hone just to make sure that the new rings have something to wear into. Even though you can see the cross hatching, there is less tooth there for the new rings to wear into.

Frog Dec 20, 2010 04:38 PM

Ok, thanks. My local machine shop will clean the block, mag check it, hone and install cam bearings for 60 bucks....cam bearings are extra thought unless I supply my own.

They also said they could grind the crank for 45...do these prices seem right??
They have been around since the early 80's

swartlkk Dec 20, 2010 08:36 PM

It's been awhile since I needed machine work done, but that doesn't sound too bad.

Frog Dec 20, 2010 11:35 PM

Should I get all new pistons or just replace the one that is damaged?? I am still looking for a kit that has rings and pistons.

Oh, the kit I listed earlier was from engine tech....they use king bearings.
Are these bearings good?

Thanks again


All times are GMT -5. The time now is 09:51 AM.


© 2026 MH Sub I, LLC dba Internet Brands