Under hood rod bearing replacement?

240Lemonade · Post by **240Lemonade** » 08 May 2012, 21:20

Is it possible, does anyone have any advice on replacing rod bearings without taking the engine out of the car? Am I a retard for thinking this thought? Please advise.

Post by **billofdurham** » 09 May 2012, 13:36

It is possible but the outside of the engine should be thoroughly cleaned as you will spend a lot of time under there and you don't want lumps of oily dirt falling on your face.

You will still need an engine hoist as you need to lift the engine to remove some of the parts.

Bill

Post by **jimmy57** » 09 May 2012, 14:20

Bill is right. The engine has to be raised to get pan off or if you drop out crossmember you have to hold engine up as crossmember is where motor mounts rest. Jack to hold up engine is VERY risky as engine is not stable without the two motor mounts supporting it side to side.

Do you know for sure you have rod bearing knock and not B230 piston knock?

240Lemonade · Post by **240Lemonade** » 09 May 2012, 14:50

Thank you both for the "good" news. I am not too worried about having to lift it up a bit, I have that covered. I have already cleaned up everything fairly well, but will give it another once over before I open her up.

This being a 1984 I am under the impression that this engine is the B23F, not the B230. I am not too aware of the differences in these two engines nor the (apparently typical) piston knock that you referred to. However, my first move when the knock appeared was to put some 20w50 oil in it which all but eliminated the knock... until I drained some out and put some Marvel Mystery oil in there which thinned it out and now the knock is back. Since this is a rhythmic noise in time with with rpms, and is kinda worst when coasting rather than under load it makes me believe it is either a rod bearing or a crank bearing. Please advise.

Thanks again for your help, I really appreciate your insight. I will post some video/audio tonight so you have a better idea of what I am up against.

Also, I know this is not your car, and you are not me, but if this problem were yours, would you bother with working on it in car or should I yank this thing and go though it entirely. 170k is alot...ish.

Post by **jimmy57** » 09 May 2012, 16:40

OOPS, I didn't look at the year. Yours is the B23. I agree that rod bearings are what it needs.
But I bet you will find a partly clogged oil pickup screen.
When you drop the pan there will be a rubber hose that comes down by oil pump. That MUST be long enough to be below oil level or the crankcase vent system will get pressure in it and not work and it will use a lot of oil.
You will have to drop drop the pan down and then remove the oil pump before the oil pan will come off unless you have the cross member WAY down out of the way. The pump goes through a hole in the oil pan baffle and it doesn't clear enough for the pan to come down at any angle if pump is mounted.

240Lemonade · Post by **240Lemonade** » 09 May 2012, 20:33

Hmmm... so, I can't post a video/audio of my knock issue because I went out today to get started and there was no more knock.?? I will take it out under load tomorrow and see if it returns or if that Marvel stuff really does work mystery miracles.

Compression came good though: front = 1? - 215psi, 2 - 220, 3 - 205, 4 - 197. This gives me even more confidence that it is/was not a piston.

jimmy57, thanks for the heads up on the oil pump, that seems like critical information that I would have gone into battle without. Thank you. Keep them coming if you have any more. This all Swedish to me.