Half compression on all 8 cylinders.

[robsco]

Cerbera is in at Track V Road, just had a call saying that the compression is half what it should be across all 8 cylinders and that she's way down on power.

I'm just on here for a moan really. We're going to try valve timing again and hope someone has bodged it in the past. After that, who knows.

[dbv8]

YHM

[C3BER]

Im sure Ian and the boys will sort it out for you very soon.

[Gazzab]

Sorry to hear that mate.
I thought the key was consistent compression across the cylinders?
Have you any other symptoms? Oil useage, smoking, coolant/oil mix, noise, power loss etc??

[julian64]

That post makes me want to ask a boatload of questions

[dbv8]

OK i cant keep quiet.

My car went there for a list of work and an MoT.
Long story short... had some issues so they did a comp test.
Their results..... 60 psi on all 8.

Took the car home, bought a tester of my own and got 145-150.
This was what was expected from my low, compression pistons btw.

[robsco]

No other symptoms, I'm told that the car is seriously down on power though. That's a very difficult thing for me to judge as I've never driven another Cerbera over anything other than a tiny distance. The car is flat as a fart I'm told!

[Gazzab]

You mentioned on another thread that you were using oil and that the oil pressure never drops below 60psi.
It really should drop lower eg 40psi when at hot idle.
I would collect my car if I was you and get a 2nd opinion.

[robsco]

That's right Gary. Don't all AJPs use oil though, to a certain extent?

[Gazzab]

robsco said:

That's right Gary. Don't all AJPs use oil though, to a certain extent?

I would say that most use oil. I had a couple that post APM rebuilds they really didnt use any at all! My current one needs a top up now and again but nothing excessive.

[Tanguero]

Gazzab said:

I would collect my car if I was you and get a 2nd opinion.

This is very good advice indeed!!! You would be very sensible to follow it immediately BEFORE authorising any further work.

[robsco]

Thing is guys, I've already told them to crack on with it.

Secondly, the car is 100 miles away and was trailered into them, to be trailered back to me. So its not just as easy as picking it up.

[dbv8]

I would drive there with a gunsons tester and check for myself!

[DAVEY DEE]

Suppose the test will be when you get it back.If its noticeably better then alls good.Good luck Rob,she's testing ya patience lately ain't she.

[dbv8]

robsco said:

Thing is guys, I've already told them to crack on with it.

Told them to crack on with what exactly?
To alter the cam timing? Strange as thats what they wanted to do to 'fix' mine.

[robsco]

dbv8 said:

Told them to crack on with what exactly?
To alter the cam timing? Strange as thats what they wanted to do to 'fix' mine.

Yes, or is it valve timing? Something to do with a potential valve leak if the clearances/timing haven't been set up properly. My mechanical knowledge isn't up with the standards of the average TVR owner so that's all I know unfortunately! Essentially the phone call was to say that they'd carried out a compression test post road-test because the engine felt so gutless compared to what is expected of a Cerbera and found some quite major deviances from the norm. 130 was mentioned, where it should be 260. The compression is also identical across all 8 cylinders.

[Gazzab]

If 130 really is a low reading for an AJP and the readings are consistent across all cylinders then cam timing does sound likely. Surely that shouldn't be mega expensive to sort?

[robsco]

No not really, its 6 hours. They did say though that if this didn't cure it then the engine is in deep st.

[dbv8]

Why would it be out that far in the first place?
Has the engine had recent work?

[FarmyardPants]

I have no reason to doubt Track v Road's expertise but nevertheless that sounds too strange to be true. I would take it to somewhere like raceproved for an assessment / dyno / tune up.

What could cause compression loss on all 8?