First engine rebuild

[LAC_STS]

As a little background this engine had a small oil leak. Oil pressure was lost while underway and engine was immediately shut off. When I checked the oil it was low but only held about a qt to get it back up to where it should be. After starting it back up it had a lower end knock.

So this engine has been sitting on the ground in my friends shop for about 3 months now.
I already got a new engine and I just got a chance to put this one on the stand and tear it down.

When I took the spark plugs out all of them except 1 had oil on them. When I took the valve covers off there was some spots where oil was where the oil had water in it. I drained the oil into a clear 8 qt bucket and there wasnt any water in it that I could see. Def not milkshake'ish. When I dropped the pan there was kinda like a crud or sludge at the bottom that was very thick and it did look like it had some water in it.

When I took the intake manifold off the oil in the intake valley had 0 water in it. The intake mani is an Edelbrock high rise. The intake mani gaskets looked ok to me but they used the rubber pieces for the front and back of the block. I read your not supposed to use the rubber pieces and you're supposed to use RTV instead.

I took the heads off and there was no headgasket problems. They were metal (SS) gaskets.
Think this little bit of waterish sludge in the bottom of the pan and the little pool in valley on the head is a problem? Could it be from the engine sitting on the floor for 3 months? The rest of the oil and places where oil was sitting looked fine no water.

Now to the big part. When I dropped the pan I took the end caps off 2 at a time and checked the bearings. I dunno what constitutes a spun bearing but I think 3 of them are spun and one (#8) REALLY bad.
Ive attached pics so you guys can tell me what you think. I can see some wear on most of them (I think) but I cant feel it, even with my nail. Obviously the two with the copper colored line I can feel and #8 was separated from the cap when I took it off cause its so shot.

So should I replace all of the rod bearings? Or just the bad ones? Should I first take the crank to a machine shop and see if they can fix it?

What do you guys think?

 

[LAC_STS]

Re: First engine rebuild

 

[Bt Doctur]

Re: First engine rebuild

a decent shop can recondition the crank like new and recondition the rods.
just have the shop order the correct size bearing

 

[Bondo]

Re: First engine rebuild

Ayuh,... If you go back, 'n Resize your pictures so they'll fit this forum,...

I'll go back, 'n read your post...

Did I mention, I HATE side-scrollin'....

 

[LAC_STS]

Re: First engine rebuild

Sorry Bondo I did resize them I guess I just put the old ones back in on accident. Ill fix it.

@Bt Doctur Thanks, do you know about how much it runs to fix the crank?

 

[zbnutcase]

Re: First engine rebuild

None of your bearings are "spun". That is what occurs when the bearing shell starts to spin in the rod or main bore, and the surrounding metal will be discolored by the heat.

 

[LAC_STS]

Re: First engine rebuild

What is the copper discoloring on some of the bearings? Is that what your talking about? I didn't see any of them spun like moved around the journal.

So the #8 one, the one that looks really bad with the copper discoloring, that ones ok? It made some decent marks on the crank that I can feel with my finger.

 

[fishrdan]

Re: First engine rebuild

Copper is the "inside" of the bearing, the outer babbit of the bearing has been worn away,,, lack of oil.

As BT said, time to visit the machine shop, grind the crank, check the rods, replace ALL of the bearings. I'd never reuse an old rod/main bearing, especially the messed up ones you pictures. Only way I'd reuse them is if they were practically new and looked new. Plus, when the crank is ground, none of the old bearings will fit anymore.

 

[LAC_STS]

Re: First engine rebuild

K thanks!

Guess Ill start taking the crank out.


Any idea on the water in the oil? again, I found water in the oil in a couple of the valleys under the valve covers, and a kinda sludge in the bottom of the oil pan that had a little bit of milky look to it. But no water in the oil I drained out, no water in the oil that was left in the intake valley either.

And there is oil on ALL of the spark plugs.

I notice on a couple of the cylinders that there will be a little bit of oil on the cyl wall. If I wipe it off then turn the engine by hand, the piston comes up, then when it goes back down it leaves a little tiny bit of oil on the cyl wall.

Does this mean the rings are bad? Could it be from me turn ing the engine upside down or something?


Thanks so much everyone

 

[Bifflefan]

Re: First engine rebuild

None of your bearings are "spun". That is what occurs when the bearing shell starts to spin in the rod or main bore, and the surrounding metal will be discolored by the heat.

No, none of these are starting to spin, but the have excess wear.

Copper is the "inside" of the bearing, the outer babbit of the bearing has been worn away,,, lack of oil.

Worn away, yes. Lack of oil, maybe.

This is in some cases, normal, but excessive wear.
Its time to rebuild, but not spun. You will know when they are spun, they are black and more often then not, not even there anymore.
By the way, as per one of the pics of the block, you did have a blown head gastket, between the 2 middle cylinders.

 

[Bt Doctur]

Re: First engine rebuild

On average:
recondition cut/polish crank, rods, new rings, new bearings, complete gasket kit runs $1000.00

 

[LAC_STS]

Re: First engine rebuild

Oh I thought it was blown if the gasket was actually broke. So that could be where the water was coming from?

Another ? If these bearings arent spun just worn, could this cause a lower end knock? The knock was barely noticeable at idle but any bit above idle and it sounded like someone was inside the engine with a hammer.

I checked all of the rods and under side of the pistons and nothing appears broken.

 

[LAC_STS]

Re: First engine rebuild

On average:
recondition cut/polish crank, rods, new rings, new bearings, complete gasket kit runs $1000.00

Sorry for all the newb questions but just wondering. do I need new rods because Ill have different size bearings after getting the crank redone?

 

[Bifflefan]

Re: First engine rebuild

Oh I thought it was blown if the gasket was actually broke. So that could be where the water was coming from?

No, its not always gone, its takes awhile to completely blow it out.
As for the water, maybe.

Another ? If these bearings arent spun just worn, could this cause a lower end knock? The knock was barely noticeable at idle but any bit above idle and it sounded like someone was inside the engine with a hammer.

Oh yea, if was just a small knock Id say your right on. Its not spun because you caught it in time. Most dont catch them until there is real damage and you can hear the knocking a mile away.

 

[Bifflefan]

Re: First engine rebuild

Sorry for all the newb questions but just wondering. do I need new rods because Ill have different size bearings after getting the crank redone?

No you wont.
When try redo the rods they make them back to the factory size, then the crank gets turned down to say .010 less and you get .010 thicker bearings to make the difference.

 

[Aloysius]

Re: First engine rebuild

Several problems I see. wiped bearings, leakage between cylinders, one piston is allowing oil into the cylinder. A leaking head gasket does not let water into the cylinder..it's the other way around. Compression pressure (2000psi or so) leaks into the water jacket.

do you really wanna get into turning the crank, etc? Maybe it's time for a new factory short block.

 

[Bifflefan]

Re: First engine rebuild

Oh, by the way, those are Fel-Pro intake gaskets. They're the best.

 

[LAC_STS]

Re: First engine rebuild

Thanks everyone


There isnt any sign of water in any of the cylinders. The engine sat on the floor of my friends shop for about 3 months and when I took the plugs out there was no rust. and there is no rust in any of the cylinders.

Theres some spots with water in the oil but the oil I drained out has been sitting in a clear bucket since last night and I dont see any water in it. The places I found water were a tiny bit in the sludge in the bottom of the oil pan and in a couple of the valleys on the heads under the valve covers.

No water in the oil that was in the intake valley.

Another thing is the intake mani on there was a Edelbrock high rise aluminum. The boat was used in salt water. There was a good bit of stuff in the water passage in the intake manifold.


I already bought a new complete engine for my boat a few months ago. this is just a project I want to do as a learning experience.



Can anyone comment on the use of the rubber gaskets on the front and back of where the intake mani meets the block?

I have read that you should use silicone or RTV or whatever and not to use those rubber gaskets. Could that also contribute to the water in the oil?

 

[dingdongs]

Re: First engine rebuild

the bores which the pistons run in are honed and this gives the effect of cross-hatching.if its visible on all bores there probably ok.a check with a micrometer on all crankshaft diameters and see if there round and within tolerance.even the scorched one may not be that bad but if theres deep grooves its best to have the lot done.if your only going to rebuild to keep as a spare for yourself a polish with some paper wet and dry a new set of shells and re.ring would probably be ok

 

[Aloysius]

Re: First engine rebuild

RTV works great, especially if the heads have been milled but not the manifold..will squeeze out thinner. I use a special grey sealer, not regular RTV.

The rod bearings didn't spin. Are the bearing shells tight in the rods? If not, they may have been beaten by too much clearance. If they're loose, the big ends may have been damaged from heat/impact and will need to be machined.

I see the corrosion in the manifold. This happens on street Vortec engines..the intake manifold corrodes and leaks.