CROSS FLOW 1600 piston rings

[uberfrog]

I have a quick question for you all mechanical wisard
It seems like I have a bad piston ring on my 1600 ford kent crossflow, since we need to open the engine should I upgrade a few things like putting lighter pistons or even bore it to a 1800 cc but keeping the same cam, I have twin weber 40 dcoe 151. Put a light flywheel if not stock from caterham or anything else worth doing. Thank you for your time
best,

N6

[Doug Liedblad]

You really need to open it up to tell for sure what the problem is. Once you open it you''ll be able to make a more informed decision.

A light flywheel is a good idea. I don't know about lighter pistons.

I have not personally rebuilt a crossflow but have been told that rebuilding them is getting expensive.

[uberfrog]

ring xflow

You really need to open it up to tell for sure what the problem is. Once you open it you''ll be able to make a more informed decision.

A light flywheel is a good idea. I don't know about lighter pistons.

I have not personally rebuilt a crossflow but have been told that rebuilding them is getting expensive.

Thank you doug for your input. I talked to Jon at caterham USA and he said that I can get all the parts at my local AUTOMOTIVE store since it is same engine as a FORD PINTO. So if it is the case parts should be very cheap, labor is a different story.

Anyway you are right, once we open the beast we will know what the problem is. We did a compression test and one cylinder is at 100 and the others are at 120 or 130 if I remember so hence the diagnostic about a bad piston ring, what is strange is that it doesn't burn a drop of oil, but one carburetor is impossible to adjust and it
's the one next to the bad cylinder.

[slomove]

That is new to me. AFAIK know the crossflow and Pinto are completely different engines. with the Pinto much bigger and heavier (I have yet to see one in a Seven) but easier to tune.

As it happened I had bad compression in my Zetec a few weeks ago. Turned out it had pitted valves and a coked piston ring. Valves replaced and piston ring unstuck with solvent and the engine runs well again.

[escondidoron]

There were two different engines installed in Pintos. The base engine for the Pinto was the 1600 (Kent) X-flow. The optional "performance" engine was the 2.0L SOHC engine. The 2.0L is often referred to as the Pinto engine. And because of the OHC configuration is is quite a bit taller than the pushrod Kent engine.

[GWise]

Probably best to do a leak-down test next since you're not sure where it's coming from. Have you ensured your valves are within adjustment?

If you bore it out, it becomes more difficult to find parts as the pinto parts don't fit anymore.

[Doug Liedblad]

The leakdown test is better than a straight compression test.

If you don't have a leakdown tester, a compression test may tell you the problem but might not. They are not reliable indicators of engine internals.

A bit of carbon stuck under a valve can give you a bad reading but won't show up when you take it apart.

Be sure the throttle is wide open when you do the compression check. All spark plugs out.

If one cylinder is low try a bit of oil thru the spark plug hole. If compression comes up it's probably the rings. if not valve. Or at least that is how we used to test.

Harbor Freight has a cheap leakdown tester but you need a compressor to use it.

YMMV

Doug

[uberfrog]

The leakdown test is better than a straight compression test.

If you don't have a leakdown tester, a compression test may tell you the problem but might not. They are not reliable indicators of engine internals.

A bit of carbon stuck under a valve can give you a bad reading but won't show up when you take it apart.

Be sure the throttle is wide open when you do the compression check. All spark plugs out.

If one cylinder is low try a bit of oil thru the spark plug hole. If compression comes up it's probably the rings. if not valve. Or at least that is how we used to test.

Harbor Freight has a cheap leakdown tester but you need a compressor to use it.

YMMV

Doug

Actually my mechanic did the leak down test from what he told me, so now we just need to open it up and see what the problem is.