p38 dse compression figures.

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bob7

bob7

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84
Location
East London
hi all, just did a compression test on my dse and got from #6, 450psi #5, 450psi #4, 44.5psi, the battery was struggling at this point so jumped it with my golf. #3, 450psi engine not cranking brilliantly but quite strong. #2, 440psi, #1,440psi my manual just states a minimum 200psi (20bar) with a 3bar tolerance, obviously my figures are better than that, but i would like to know how good, if anyone knows the highest figures i would appreciate the info, thanks
 
bob7 said:
hi all, just did a compression test on my dse and got from #6, 450psi #5, 450psi #4, 44.5psi, the battery was struggling at this point so jumped it with my golf. #3, 450psi engine not cranking brilliantly but quite strong. #2, 440psi, #1,440psi my manual just states a minimum 200psi (20bar) with a 3bar tolerance, obviously my figures are better than that, but i would like to know how good, if anyone knows the highest figures i would appreciate the info, thanks
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Hope that figure for number 4 is a typo, if not you have a problem:eek:
 
how are those figures data ?, im looking to give this vehicle a good going over, shes in very good shape anyway and i intend to keep her, also is there a way of re-channelling the breather filter from cam cover to air intake duct to stop the oily smear entering the intercooler system, maby to a catch tank or bottle? like we did on our race bikes.
 
bob7 said:
how are those figures data ?, im looking to give this vehicle a good going over, shes in very good shape anyway and i intend to keep her, also is there a way of re-channelling the breather filter from cam cover to air intake duct to stop the oily smear entering the intercooler system, maby to a catch tank or bottle? like we did on our race bikes.
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Wammers is the expert on compression figures, but yours would seem to be good.
You should not mover the breather, it maintains negative pressure in the crank case. The oil does no harm.
 
thanks data, ive got a doner motor in bits and change the intercooler and clean all hoses and the ally intake manifold when i think she needs it, if there was another way it would of saved a bit of time but its no big deal, the clean set i put on and then clean the dirty set ready for next time,
 
bob7 said:
thanks data, ive got a doner motor in bits and change the intercooler and clean all hoses and the ally intake manifold when i think she needs it, if there was another way it would of saved a bit of time but its no big deal, the clean set i put on and then clean the dirty set ready for next time,
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It doesn't get that bad, clean every 50K miles. The EGR causes much bigger problems but yours doesn't have that piece of crap.
 
yes mine is none egr, but it does get ,maybe a bit to oily (which is now a concern ) as it seems to come from the filter breather down through the turbo which is new through intercooller rad through to the inlet manifold and back into the air fuel mix which i thought would make for a smokie situation thats why ive been changing the rads over twice a year, im using 5/30 fully synthetic, (do you think this is too thin,) but in two weeks im changing to a mineral, its slightly smokie from initial pull away then its clear and a puff when kicking down, but when ive changed intercooller rad cleaned hoses and intake manifold theres no smoke at all from pull away and foot down ,right through the box, this will last a good few months and , then that little puff of smoke shows its face again, this is my first p38 which ive had about 2&half yrs but ive had a couple of discos, and never had this situation,is it normal ? or am i getting to fussy its a 1997 dse auto with a 40,000 mile omega transplant engine. my mates vogue its a 99my and chipped and he boots it every where and not a bit of smoke jammy sod.
 
bob7 said:
yes mine is none egr, but it does get ,maybe a bit to oily (which is now a concern ) as it seems to come from the filter breather down through the turbo which is new through intercooller rad through to the inlet manifold and back into the air fuel mix which i thought would make for a smokie situation thats why ive been changing the rads over twice a year, im using 5/30 fully synthetic, (do you think this is too thin,) but in two weeks im changing to a mineral, its slightly smokie from initial pull away then its clear and a puff when kicking down, but when ive changed intercooller rad cleaned hoses and intake manifold theres no smoke at all from pull away and foot down ,right through the box, this will last a good few months and , then that little puff of smoke shows its face again, this is my first p38 which ive had about 2&half yrs but ive had a couple of discos, and never had this situation,is it normal ? or am i getting to fussy its a 1997 dse auto with a 40,000 mile omega transplant engine. my mates vogue its a 99my and chipped and he boots it every where and not a bit of smoke jammy sod.
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Put some thicker oil in, maybe 10 W 40. See what you get. No need for fully synthetic oil in it at all, just as good with mineral or semi synthetic and change more often. The stuff you are using is like rat pee, good for running in Alaska in winter but to thin for here. Oil in the intercooler is normal.
 
thanks wammers, yes it is **** weak, ive read loads of threads before posting mine over a few weeks and your info is very helpfull and wellcome, i was going to PM you as data said your the man to ask about my compression figures, what do you think ? also how do i check the oil ways in the head that supply the cam and tappets, last year i had a tappet noise around 4&5 cylinder so replaced all tappets, the noise was still there and exactly the same,the exhaust manifold gaskets aint letting by so maybe it could be a blocked oil way around that area ? do you think thats posible
 
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wammers said:
Put some thicker oil in, maybe 10 W 40. See what you get. No need for fully synthetic oil in it at all, just as good with mineral or semi synthetic and change more often. The stuff you are using is like rat pee, good for running in Alaska in winter but to thin for here. Oil in the intercooler is normal.
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+1 on the oil
 
yeah thanks druim, thats what you get listening to the local stealer, looking at a lot of threads on here i was thinking of a mineral oil 10/40 but is there any given make that is a good mineral oil ?, i will be changing it regularly along with the filter
 
bob7 said:
by the way druim seeing as no body has answered the compression figure question, what do you think ?
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Good and most importantly even,
I use Shell Helix 10W 40 HX7, change minimum twice a year. cost peanuts for the pleasure of a golden dip stick and engine doesn't mind either :)
 
bob7 said:
thanks wammers, yes it is **** weak, ive read loads of threads before posting mine over a few weeks and your info is very helpfull and wellcome, i was going to PM you as data said your the man to ask about my compression figures, what do you think ? also how do i check the oil ways in the head that supply the cam and tappets, last year i had a tappet noise around 4&5 cylinder so replaced all tappets, the noise was still there and exactly the same,the exhaust manifold gaskets aint letting by so maybe it could be a blocked oil way around that area ? do you think thats posible
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Compression should be a minimum of 20 bar that is 294 PSI. Cylinders must be within 44 PSI of each other. So if the compression cannot be below 294 PSI with a permitted 3 bar deviation that is putting minimum acceptable compression around 339 PSI. If you are getting 450 you have either a very sound motor or a duff pressure gauge. :D:D
 
bob7 said:
yeah thanks druim, thats what you get listening to the local stealer, looking at a lot of threads on here i was thinking of a mineral oil 10/40 but is there any given make that is a good mineral oil ?, i will be changing it regularly along with the filter
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i use asda 10/40 oil i buy it when its on offer at a tenner a gallon its worked ok for me :D
 
thanks wammers, pressure gauge is correct was recently calibrated (sykes-pickavant) from my friends workplace where its used regularly, what would be the max figure that could be achieved ? or am i nearly there?
 
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