Compression test results advice

[harin 0]

Hi guys,

 

Finally got my mechanic in to do a few compression tests on the VR6 (Could have done it myself but wanted to them to be accurate). Brief history:

 

Put in Rotrex kit myself last year >> Took it to Storm for a session on the rolling road >> BHP was lower than expected >> They did a compression test and said one cylinder was too low and that the engine needs replacing >> I've been trying to get the car running so my mechanic can take a took.

 

This is what he got:

 

Cold

1. 160

3. 162

5. 151

2. 170

4. 171

6. 168

 

Hot

1. 161

3. 163

5. 155

2. 172

4. 171

6. 170

 

Oil Test

 

1. 207

3. 204

5. 205

2. 210

4. 212

6. 212

 

Just wanted to check the results with you guys and see what you think is the cause. Obviously want to try and keep the car but can't afford to rebuild the engine yet. My mechanic says the engine is worn and its probably the piston rings. What do you lot think? Any similar readings where your 'oil' tests were consistently that much higher than 'hot' tests?

 

The only thing I've noticed is that engine is running hotter than normal and fan kicks quite frequently. Also a slight power loss at the top end.

 

(Not the happiest with Storm I must admit. After spending £1500 with them on the kit, then being told 'Get a new engine' then them offering me a R32 then not ever returning my calls!)

[Kevin Bacon 5]

They're all down. Should be up in the 180s.

 

5 is the worst but overall it's not spectaculalry bad to be honest. I've seen worse. I would get a leak down test done just to confirm it's not valve or guide wear. Rebuilding a head is obviously far cheaper than the replacing the whole engine!

[harin 0]

Thanks for that...so will the leakdown test also confirm if its the piston rings too?

[Kevin Bacon 5]

Yep!

[harin 0]

Great thanks again! Will need to find a decent mechanic then

 

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[bruny 0]

Dont think these compression results mean an engine rebuild is required, they are well within tolerance still, perhaps lower output is showing another problem such as air leak / mixture, injectors etc. :shrug:

And if youre looking for a good mechanic/specialist I would recomend DG Autotech, two for the price of one :notworthy:

[Leonard 0]

Out of interest how much is a head rebuild on a VR nowaday?

[harin 0]

And if youre looking for a good mechanic/specialist I would recomend DG Autotech, two for the price of one :notworthy:

 

Thanks for the recommendation but I'm in London so going to be tough to get down there in SORN'ed and not MOT'ed rado! Probably get pulled before getting on the M1 :)

 

My usual mechanic doesn't have the equipment so will need to have it done somewhere locally then post results here and ask for more help! Can't trust anyone these days!

 

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