Technical How do you replace pistong rings without removing engine?

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Technical How do you replace pistong rings without removing engine?

no they wont be out, the clearances should actually decrease, because the bearing shells will be new.

as long as you get the correct bearing shells its fine.. it will say which bearing shells you need on the old 1s its stamped on it.

bearing shells are quite important to oil pressure, when they wear too much you loose your oil pressure... which is why most people change them while the bearing caps or off, just means its 1 less thing to worry about in the future, and with a better oil pressure less internal wear.

only time you dont change bearing shells is if the crank is all scored up.. but this would be quite a serious problem if bad enough and would require a crank regrind, and the old bearings wouldnt help things.
Ok so new big end bearings, what about the con rod bearings/shells ? they should be good?
 
Big end bearings are the lower conrod bearings. They are a split bearing in 1 halves which you can replace when you remove the bearing caps to remove the pistons.

upper conrod bearings or small end bearings you cant change because these are pressed into the conrod.

Main bearing shells are the crankshaft carrier bearings.. what hold the crankshaft to the block.. cant change these eigther without removing the crankshaft.

but to change half the bearings is better than none at all.

I do recommend though that you dont try doing this with the block in the car, the reason why its done with the block out is because if the engine is so worn it needs new rings, there maybe other components that are worn.. bores might even be too worn to take new rings, or at the very least require honing to ensure the rings seal properly. So engine builders take this opportunity to inspect the components of the engine, and change any leaking seals/gaskets, and its also important that no dirt gets in the bearingshells when you re-install the pistons.

But you cant get the bores honed with the block in the car as it has to go on a machine.
If you put new rings in, and later on find it hasnt cured the problem you will have to pull it all apart again, and if the cost of a rebore is too much may find the engine is scrap.
 
If your short of money why not look on ebay for replacment engine, can pick one up for betwwen £50-£100. You can then have the other engine to take apart and learn from, recondition at your own time. If your girlfriend works in a garage then im sure they would let her borrow an engine hoist for a day or two to swap them out..
 
If your short of money why not look on ebay for replacment engine, can pick one up for betwwen £50-£100. You can then have the other engine to take apart and learn from, recondition at your own time. If your girlfriend works in a garage then im sure they would let her borrow an engine hoist for a day or two to swap them out..
i live in london she lives in kent :(
but if it still is burning oil after i might consider replacing the engine for en ebay one.. i have found some cheap ones with 65k etc, mine is 85k...
 
Hi, piston ring sets arent terribly cheap.

If you are going to go ahead it needs to be done properly so your not wasting your money. If you do go ahead though your engine would be in better condition than one on ebay.. but only if its done properly.

Also, if the bores are beyond standad ring size in terms of wear.. a professional check will allow you to make an informed descision.. ie, getting a replacement engine before buying a piston ring set.
 
Compression test shows piston rings are fine, but are these normal ? in order of cylinders... 213psi 209psi 219psi 219psi :confused:
It seems it's burning water/coolant, not oil 'anymore'...
new head or get it skimmed methinks
 
The 209 looks odd, but its within a reasonable range of the 219s so nothing to worry about.

Have you just not rebuilt the head?

Cheers

SPD
yeah, but after 2 weeks it started to smoke. thought it was oil at first but it was coolant... it randomly stopped smoking for a second and slowly came back. i think its strange
i know i should'a had it skimmed in the first place so dont moan at me for that ol, but i thought it'd be alright ... ah well !
 
The 209 looks odd, but its within a reasonable range of the 219s so nothing to worry about.

Have you just not rebuilt the head?

Cheers

SPD
I'm lookin at a head on ebay and was wonderin if a 1200cc would work with my engine? sorry if it's a silly question haha! i thought maybe the blocks are different but heads similar in the 1080/1200cc engines?
 
yeah, but after 2 weeks it started to smoke. thought it was oil at first but it was coolant... it randomly stopped smoking for a second and slowly came back. i think its strange
i know i should'a had it skimmed in the first place so dont moan at me for that ol, but i thought it'd be alright ... ah well !

Well take it off again, and get it pressure tested then, if ok, get it skimmed.

Cheers

SPD
 
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