found out why there was no compression

**t5 pete** · Tuesday 15th June 2010, 22:14

Well finally found time to take the head of my t5 and find out why i had no compression.
Well got the head off to discover a large chunk of the exhaust valve face missing so no wounder there was no compression will hopefully get it built back up at the weekend.
I will upload somepics tomorrow hopefull when i get the camera working.
Im just happy the piece much have gone dowm the exhuast and not droped in on the piston as that would have been another story.

**ANDY B** · Tuesday 15th June 2010, 22:25

What causes this? dodgy injector or low fuel pressure? not enough fuel, running lean and heating the exhaust valve?

another post LUMPY just ate 2 exhaust valves

**t5 pete** · Tuesday 15th June 2010, 22:29

it could be a number of things metal fatigue, heat, wear and tear, valve bounce etc
Whos lumpy?

**fireclown** · Tuesday 15th June 2010, 22:36

i would check your turbo. of its gone out the exhaust port. its gone through the turbo.

**t5 pete** · Tuesday 15th June 2010, 22:52

turbo is working fine so hasnt caused any major problems, it/ might have bent a few fins but havent cheaked them

**ANDY B** · Tuesday 15th June 2010, 23:21

lumpy is the name of another similar thread by snarko snarko

**rocket ronny** · Wednesday 16th June 2010, 19:36

Originally Posted by t5 pete

turbo is working fine so hasnt caused any major problems, it/ might have bent a few fins but havent cheaked them

bent a few fins ??? WTF,s a "fin."??..., if a section of exhaust valve has gone through the turbo then your going to have serious damage to the turbine blades

**t5 pete** · Wednesday 16th June 2010, 20:57

Originally Posted by rocket ronny

bent a few fins ??? WTF,s a "fin."??..., if a section of exhaust valve has gone through the turbo then your going to have serious damage to the turbine blades

I was using the word fins meaning blades, and the section of the exhaust valve has gone throungh the hot side housing and not flowing throught the compressor housing, and as i said the turbo is working fine by not smoking and still ready to build boost but i have to check the exhaust turbine as it will have most likley has damaged the fins/blades.
I hope this clears this up for you and next time keep a open mind instead of throwing your WTF just because some one has called them a different name doesnt mean they are not on about the same thing. heres a picture for you and if you see the red arrows that is the direction the piece will have gone.

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**t5 pete** · Thursday 17th June 2010, 22:07

abit of a update decided to fit another head which i had laying around ive also removed the turbo and theres no damage at all and no clyinder or piston damage so been very lucky here a couple of pics.
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**fireclown** · Thursday 17th June 2010, 22:45

looks like it has been a valve seating problem and the valve has burnt away. maybe running a bit lean.

**t5 pete** · Thursday 17th June 2010, 22:53

Thats the main reason i have used a different head as i didnt want any further problems with this one I have noticed an inbalance in the running of the clyinders as two of the plugs are pink colour but on the other plugs there a lovley chesnut brown going to have the injectors cleaned to make sure there all flowing the same if there no major imbalance there ill check the power supply to them

**t5 pete** · Sunday 20th June 2010, 20:59

well all back together and running lovley im just woundering how many other people have had this problem as i know of 4 up to now also i have always used tesco super unleaded 99 octain and have noticed in the past month the have changed for there own tesco brand to another one.
The clyinder that went down wasnt runing lean at all, if any one has any info on the cause of this i would be greatfull to hear you oppinions also any of the traiders on here have you come accross this much and have you got any info on the subject.
Cheers pete

**leet5r** · Sunday 20th June 2010, 22:33

Originally Posted by t5 pete

well all back together and running lovley im just woundering how many other people have had this problem as i know of 4 up to now also i have always used tesco super unleaded 99 octain and have noticed in the past month the have changed for there own tesco brand to another one.
The clyinder that went down wasnt runing lean at all, if any one has any info on the cause of this i would be greatfull to hear you oppinions also any of the traiders on here have you come accross this much and have you got any info on the subject.
Cheers pete

could just b bad luck m8. old age and wear and tear , pm,ed

**t5 pete** · Monday 21st June 2010, 07:44

it just seems too much of a coinsidence for 4 of the same cars to have the same problem all around the same time

**cookie** · Monday 21st June 2010, 10:04

I had exactly the same, about 5 years ago, just turned 100,000 miles, replaced all exhaust valves, and not had a problem since, there was no sign of a reason why, everything else was fine, checked compression last thursday at Tim's and all cylinders were between 150 and 155

**leet5r** · Monday 21st June 2010, 10:20

could the injectors m8. A think mine could be on its way like . Because a done a comp test and all were 150 apart from 1 which was 125

**t5 pete** · Monday 21st June 2010, 22:18

I really do belive it was s**t fuel that has caused the problem also i did a compresion test less than 1000 miles before the valve got burnt and every clyinder was 12.5 bar which is brilliant.
I was talking to a bloke the other day who worked in the fuel business and he was telling me that i wouldnt believe what crap goes into the fuel we use.

**RT MECHANICS** · Tuesday 22nd June 2010, 21:37

Hi Pete

I can beat you !!!!

Looks like you have been unlucky as i had not seen that happen on a T5 engine ever until last week inlets this time though :

BUT not one cylinder but 2...

Glad you got it sorted

**t5 pete** · Tuesday 22nd June 2010, 21:47

Hi russ that makes it the 5th one i know about theres certanly something gone wrong at least mynes back up and running

**nobananas** · Tuesday 22nd June 2010, 21:54

Weird thing regarding supermarket fuel. My missus uses Tesco's stuff in her T5, has done for years and does around 70 miles a day with no (touch wood !) problems. I work at a small independent which has a filling station attached, my boss slates supermarket fuel (which he would !) yet the delivery driver has said that in the case of super-unleaded it all comes from the same tanks at the depot !!. Interestingly though has anyone noticed that Tescos 99 ron has been re-labeled just recently ?