align 700 / align 91H engine question

[dieselcarb]

If the engine is dry then it will feel like theres not much, most car engines are ABC so don't normally have a ring. If the engine is wet still with fuel then maybe as Kev has said above

Abc engines are compression junkies with the exception of irvines. U wanna feel an engine with a dykes ring no compression at all until it fires and warms up a bit.

[KevDavies]

are you confusing pinch with compression here?? I always felt ring engines had more compression. But ABC's have loads of pinch which feels like compression when you turn it, but not if you put a guage on top

[ditonics]

You're right I'm thinking of the pinch on the ABC engines - used to run OPS PRO fully gasflowed and tuned within an inch of its life and it had a lot of 'pinch' with new piston and liner.
The 91H has little compression when turned over by hand but produces loads of power and is nigh impossible to turn over hot and wet (no puns please lol)

[panosg]

I will be interested to know if there is a compression gauge/tool to fit those engines.
Surely that way would be the best way to find out if the compression is down or not?

[KevDavies]

I made an adapter Panos. and use a motorbike compression guage

[panosg]

I made an adapter Panos. and use a motorbike compression guage

I am thinking on those line too!
Is there a set guide on what the compresion needs to be on most of the engines?

[KevDavies]

about 7:1-9:1 is a good figure for a 2 stroke mate

[ditonics]

Crank finally out, was easy in the end could grip the fan with a rag and undo the nut with a socket. No locking tools needed.

Bit stuck with the carb though, I cannot get it out. The pinch nuts are out and the carb will rotate, but it will not pull away from the crank case.
Any ideas. I cannot put it in the oven with the carb on

[dieselcarb]

Put the bolt back in but not all the way and then tap it. It should pop that half free.