Compression Test

[hemibum]

Here's a set of compression test numbers from a Fordie X Flow. Interpretations anyone?

All figures taken with throttle wide open .

Cold Engine

1 150 psi

2 150 psi

3 150 psi

4 150 psi

Engine at working temp.

1 175 psi

2 170 psi

3 175 psi

4 175 psi

Again at working temp, but with a few CC's of oil added.

1 240 psi

2 240 psi

3 220 psi

4 235 psi.

Looking forward to your comments.

[hemibum]

Well, thanks for that. Still doesn't explain the amount of oily fumes coming out of the breather!

Looking at the possibility of wrong dipstick allowing too high an oil level.

[hemibum]

Thanks Stevie, this engine has only done about 500 miles in the last 7 years, and now , although it idles and revs beautifully it chucks so much st out of the breather.

[hemibum]

I had run a pipe from the breather outlet into a plastic bottle as a half assed catch tank.

Since I've done away with that it's running fine again. The bottle must have been creating a back pressure in the system somehow. Whatever, the problem is vanished, gone, end of.

[hemibum]

smckeown said:

hemibum said:

I had run a pipe from the breather outlet into a plastic bottle as a half assed catch tank.

Since I've done away with that it's running fine again. The bottle must have been creating a back pressure in the system somehow. Whatever, the problem is vanished, gone, end of.

Sounds like the engine needs a breather outlet as well as a method of capturing/recirculating any oil

I recently designed/improved my existing system here:




Cam cover breather oulet was previously located above cam and not baffled...bafling design!


Here's Burton Power's excellent technical article on the subject that I used:
http://www.burtonpower.com/technical_1/engine_brea...

Thanks for that, and I've got the Burton catalogue which describes the breathing set ups.

I have to admit that I was being a bit sneaky in describing the engine as a crossflow.

Yes it is a Xflow block but with a Lotus twin cam head on it. I just got fed up with posting anything referring to TC's and getting so much hassle from the "Lotus" bunch.

At the end of the day it's the same engine, and apart from the head and water pump it's a X flow as punted out by old Henry.