need some advice!

[gtirjaymz]

hi
Back again with yet more problems.:evil: I got a rebuilt engine about a yr ago but have only just fitted. Other day i drove my sar for 1st time in 2 yrs. Only went 300 yrds tho cuz it was missfiring. checked plugs, leads etc, all ok. the pressure tested. There is only 25psi in cylinder 4!! all others ok. so i jus rang the guy i got it off, he said as the engine has been standing for so long the valve might have stuck open thus giving no pressure... is this true?? he sed it may have got some moisture inside???
he told me he's never had anybody have any problems before or had to use their warrenty.
i hope he's telling me the truth as i want to believe wot he says... i just want my sar back so i can sell it.
Pls can u give me advice (technical or none) lol or tell me wot it cud be?

cheers all
james:evil:

 

[youngsyp]

Yep, it's more than possible that a valve or two is stuck open, with having the engine sat about for so long.
Your best bet is to take the head off to confirm it and remedy the problem. If you run the engine, with a valve stuck open, you could risk bending said valve and/or damaging the piston, then bore etc.....

 

[pulsarboby]

highly unlikely that a valve is stuck open, and if it was, then it will be a bent valve, as the piston would hit it on either induction or exhaust stroke!
more than likely cause is a seized ring. take the plug out of cylinder and squirt a load of penetrating oil down the bore, and hopefully if it is that, then it will free the seized ring!

you can check valve movement by removing rocker cover and turning engine over by hand to make sure the valves are all moving up and down correctly!

i hope for your sake that it is just a seized ring, and nothing more sinister!

 

[youngsyp]

highly unlikely that a valve is stuck open, and if it was, then it will be a bent valve, as the piston would hit it on either induction or exhaust stroke!
more than likely cause is a seized ring. take the plug out of cylinder and squirt a load of penetrating oil down the bore, and hopefully if it is that, then it will free the seized ring!

you can check valve movement by removing rocker cover and turning engine over by hand to make sure the valves are all moving up and down correctly!

i hope for your sake that it is just a seized ring, and nothing more sinister!

If it was a seized ring, surely the piston would not move, when the engine ran ?
He'd be in big trouble then as, the rod would probably come through the block !!

I like the idea for checking the valves though !

Thinking about it, it could be a valve that hasn't closed properly as, if the valve was syuck open, not only would it now be bent, as explained above but, you wouldn't even get 25 psi compression, would you ?!

 

[PaulB]

strange as its cylinder 4, as this is the one that gets the least air, and is more prone to DET etc.

 

[pulsarboby]

the piston would move freely, but the ring would be seized on journal of piston, will not be seized onto bore!

this wont cause the rod to come through block, the only way that would happen, was if the bigend bearing spun which would cause the holder to be pushed or ripped off the conrod, then wallop! 'straight through side of block'

and as you rightly say, if the valve was the prob, then you would have 0 compression on that cylinder.
although it is possible that its seating isnt airtight, which will cause loss of compression, but i doubt very much, that this is the fella's problem here!

 

[gtirjaymz]

cheers for the replies guys!
i went down to the car earlier and did a different compression test on the no4 cylinder (i think its no4, on far right anyway). This time putting air into it. found that air is coming out of the oil dipstick. you think this is a problem with piston rings? i got the engine from JRN performance in wales, any1 had a recon engine off em?? wot shall i try next? and if that doesnt solve it what after that?
can any1 tell me about the ecu check thing? id like to know about the inbuilt airfuel meter. how do u tell weva its lean or rich??
cheers peeps!

 

[pulsarboby]

def rings!
try what i suggested earlier, with penetrating oil down the plug hole, and leave it overnight!
if that dont work, then you have major probs.

 

[steven_c]

it'll be like a steam train when running throwing the air in to the sump and blowing out of the dip stick ( head off time, pistons out )

 

[KF79GTIR]

I got the engine from JRN performance in wales, any1 had a recon engine off em?? wot shall i try next? and if that doesnt solve it what after that?
can any1 tell me about the ecu check thing? id like to know about the inbuilt airfuel meter. how do u tell weva its lean or rich??
cheers peeps![/QUOTE]


I have spoken to james from JNR in wales quite a few times and he will be rebuilding my block in the next month or two i know of a couple of people that have had work done by him before and the engines he builds are to a good spec and even better standard have you tried talking to him about it and resolving the issue i know his prices are very good compared to other rebuilders. :suspicious:

 

[gtirjaymz]

hi again,

i just checked all the plugs and the one on the far right looks as if it hasnt been used, no black on it like the others. injector problem???? but if so, why only 25-75 psi??
i pressure tested all 4 cylinders from left to right... 125psi 100psi 100psi 75psi
i left like wd40 stuff in far right cylinder overnight but no joy. did ecu check and got 34 which is det sensor circuit. this is doing my head in now any clues????
cheers
jimbo.

 

[Fast Guy]

Going by that compression test, your whole engine is fooked.

 

[Bart GTI-R]

Hi there mate,

Replied to your PM but as fast guy says your engine doesnt seem to Healthy, the PSI should be around 165 with the pressure test (try another gauge to start with) as regards to cylinder 4 it defo sounds like the rings. Carry out the leak test on all cylidners (at top Dead Center) dont forget to put it in gear and have the handbrake on. listen to the Inlet pipe from the plenum and exhaust, also remove the oil filler cap and see whats leaking may be that the valves arent seating properly as well as ring problems.

You could also use a Miti Vac gauge to check engine faults but dont use the Dump Valve vac pipe as this is ported and not direct, you need the pipe after the throttle bodies (engine side) I used the pipes behind the rocker cover the one to the left next to the rocker breather (o/s from car point of view) but it was a bit of game to get back on.

hope this helps (anyone correct me if iv put anything wrong)

Gregg

 

[sumo]

go with what pulsarboby is saying put loads off it in u could tri some of that rust frezze stuff its really good as for the rest off them being bit low they might need some spray as well and it a new bulid engine the ring will not be right run in so might ont seal right

 

[pulsarboby]

there is one other possibility!
the valves could possibly be overshimmed (although i coulnt see an engine builder making such a huge mistake tbh)
ok, pour a teaspoonfull or two of engine oil down each plug hole in turn, then compression test each cylinder (wet test) straight away!
if compression rises, then its definately worn rings!
if compression stays the same, then you have a valve problem!

either way, its time to get stripping (unless of course its overshimmed, and not allowing valves to fully close);-)

 

[gtirjaymz]

cheers for all the replies u lot! i can tell some of you know ur stuff!!

The guy at JRN performance said he'd have a good look at the car to find out the problem for free but i have to take the car to him :doh: hopefully he can sort it out tho. I need a trailer!!!

 

[KF79GTIR]

cheers for all the replies u lot! i can tell some of you know ur stuff!!

The guy at JRN performance said he'd have a good look at the car to find out the problem for free but i have to take the car to him :doh: hopefully he can sort it out tho. I need a trailer!!!

Thats good of him how far do you have to travel from to get your R to him. Where are you based. just a thought if you let your car warm up for a few mins then pull your dip stick out half an inch or so &rev the engine and you see smoke pour out your dipstick hole then it is definatly your piston rings that are shot

 

[gtirjaymz]

im nr uttoxeter which is between stoke and derby. need to take it to swansea.
how can i get it ther guys???????? :?

 

[KF79GTIR]

im nr uttoxeter which is between stoke and derby. need to take it to swansea.
how can i get it ther guys???????? :?

Give him a call at JNR and see if he can help you out if not try every one in the yellow pages or local phoe book until you get the best price on a flatbeb transporter...

 

[pulsarboby]

go and join the aa (relay cover), drive it up the road away from your house, and tell them its broke down, they will recover it to swansea for you if you say you want it taken there, as there the people that built the engine for you;-)