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Effect to engine if Valve stems seals are not repaired


Samurai 20V

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Hi..

 

So my 2JZGTE motor is starting to show signs of worn valve stem seals, there is a slight puff of blue smoke on start up, somedays it throws out a bit more, but not huge plumes..

 

If I just leave it alone, what is the effect to the motor in the long run?

 

If I do decide to overhaul, I would probably take the head off. Is it recommended to renew the rings and bearings at the same time, or no need just leave it alone? Any other items that should be changed whilst the head is out?

 

Thanks.

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Other than the annoyance of lots of smoke it wont damage the engine as it gets burnt off.

If you were to change the rings and bearings you would need to pull the engine out, but unless you have problems with compression, oil consumption etc or plan to run big power the stock rings and bearings will be fine

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I'd get a compression and leak down test done first, if there good then no real need to take

the head off and you can change the stem seals either using the rope trick or

compressed air method.

 

I'd think over a long period of time you could get a bigger carbon build up if their not changed.

 

As said above if you want to change rings and bearings then you need to remove the engine

and then your into stripping it totally so might as well fit new oil pump etc etc

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I'd get a compression and leak down test done first, if there good then no real need to take

the head off and you can change the stem seals either using the rope trick or

compressed air method.

 

I'd think over a long period of time you could get a bigger carbon build up if their not changed.

 

As said above if you want to change rings and bearings then you need to remove the engine

and then your into stripping it totally so might as well fit new oil pump etc etc

 

I think thats a good idea... If the rings are sealing properly might as well leave the assembly alone and change the seals in place.

 

For now it is not annoying me, but if it does start to get worse the I would look to replace the seals....

 

If I do decide to take the head off then I would decide to freshen up the bottom end and most likely do a turbo upgrade at the same time....

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I think thats a good idea... If the rings are sealing properly might as well leave the assembly alone and change the seals in place.

 

For now it is not annoying me, but if it does start to get worse the I would look to replace the seals....

 

If I do decide to take the head off then I would decide to freshen up the bottom end and most likely do a turbo upgrade at the same time....

 

My car was running fine in every way so i decided if the test results were good i'd leave well alone and just

replace the seals with the head on which is what i did as the results were very good so no need to touch

 

If there not then i'd pull the engine and do a full rebuild inc the turbos

 

Or drop a built motor in there :)

Edited by Dnk (see edit history)
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My car was running fine in every way so i decided if the test results were good i'd leave well alone and just

replace the seals with the head on which is what i did as the results were very good so no need to touch

 

If there not then i'd pull the engine and do a full rebuild inc the turbos

 

Or drop a built motor in there :)

 

Yeah, I think thats the best idea..

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Yeah, I think thats the best idea..

 

I should of added if your numbers arent great then the leakdown test should pin point where the problem lies be it, inlet valves, exhaust valves or cylinder bores/piston rings.

 

If it showed to be valve leakage then you could just take the head off and get it rebuilt saving you the expense of a full

engine out job.

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I should of added if your numbers arent great then the leakdown test should pin point where the problem lies be it, inlet valves, exhaust valves or cylinder bores/piston rings.

 

If it showed to be valve leakage then you could just take the head off and get it rebuilt saving you the expense of a full

engine out job.

 

Good point...

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  • 1 month later...
hmmm is it an expensive job getting the head and valves sorted?

 

sometimes im a little embarassed with a bit of blue when starting from cold now and again

 

I think someone was quoted about £1,000 to have them changed. I'd opt to do it myself and just take my time over it..

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a grand..... blimey

 

This is one of the jobs though that people balk at, just like refreshing suspension arms - lots of cost where you can't put a bhp figure against.

 

It's a maintenance job for quite a while, but as said if you've got badly coked exhaust valves, one bit flying off could knacker your turbo/turbos one day.

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