How to Do a Dry and a Wet Compression Check?

R

Rudi

501 Club
guys:

Bear with me...

I know basically that if I take a plug out, insert the compression tester and then hand crank the engine over, I can get the compression on each cylinder. Pretty basic.. even for a dummy like me....

Now, please explain to me what a Dry check is and what a Wet check is?

Dry - is that before I put in the oil?

Wet - is that after I replace the oil?

I am at the point where most of Ellie is back together. Yeah, it has been a bit, but between the wood and other stuff... I haven't had as much time as I would need or like to play on Ellie. Although there is something to be said for lots of grease, oil and dirt on one's hands.

I am going up for lunch. Will check back in a bit. Then I am hoping to do the compression check.... I have my fingers crossed.

Oh, btw... what do I put on the paper gasket that goes under the Oil Filter Housing Cover? Or is it put on dry? I had a heck of a time cleaning the other one off....

Oh one other question. With the price of anti-freeze going through the roof right now, and I just added 3 quarts to Ellie before I drained the system, can I filter the coolant and reuse? The hydrometer says it is perfect.... what do you think?


TIA
 
Yes, dry is without oil and wet is with oil.

I put a thin film of oil on the gasket, but I doubt if it's necessary because it's force of habit from putting a film of oil on the spin-on filter gaskets.

You should change the coolant. Unless you add water or pure antifreeze to it, the density of your coolant won't change. But the pH changes over time (it becomes acidic) and filtering won't remove all the impurities it collected from the boogered head gasket problem.

Good luck!

PS, remove all four plugs and open the throttle and choke for the compression test.
 
Electric starter if you engine has one. You should do at least 4 compression strokes per cyliner to get a compression reading.

Hand crank. Try to get 4 compression strokes. The readings will be lower than with the electric starter.

My opinion, I would reuse the antifreeze.

Eugene
 
Rudi":19dyuh3o said:
guys:

Bear with me...

I know basically that if I take a plug out, insert the compression tester and then hand crank the engine over, I can get the compression on each cylinder. Pretty basic.. even for a dummy like me....

Now, please explain to me what a Dry check is and what a Wet check is?

Dry - is that before I put in the oil?

Wet - is that after I replace the oil?

I am at the point where most of Ellie is back together. Yeah, it has been a bit, but between the wood and other stuff... I haven't had as much time as I would need or like to play on Ellie. Although there is something to be said for lots of grease, oil and dirt on one's hands.

I am going up for lunch. Will check back in a bit. Then I am hoping to do the compression check.... I have my fingers crossed.

Oh, btw... what do I put on the paper gasket that goes under the Oil Filter Housing Cover? Or is it put on dry? I had a heck of a time cleaning the other one off....

Oh one other question. With the price of anti-freeze going through the roof right now, and I just added 3 quarts to Ellie before I drained the system, can I filter the coolant and reuse? The hydrometer says it is perfect.... what do you think?


TIA
Click to expand...



Rudi,
Please tell me you did not crank the poor cub over with no oil in the crank case!!!!!!!!!!!!!!

A dry test is pull the plugs all of them roll the eng. over usually 10 times.
Read gage.
Wet test put oil in thru plug holes (about 4 pumps of a good oil can or about 1/2 to 1 oz.
Roll eng. over 10 times as above read gage.
compare readings .
If diff. is more than 10lb you need to rebuild you even go 15lb diff.
 
Dale:

No, I did not crank it over without oil in her. That is why I was asking. Before I turned her over, I made sure all the fluid levels were up. Still haven't done the compression test, had to put the hood on and get Ellie out of the shop. Lawn had to be done and the JD was in the finishing room squeezed between the Cub-54 Blade, Steel racking and Ellie...

Will get to it, but I can say this, Ellie is runnin good!
 
I always pull all the plugs when I do a compression check. The engine soins faster and saves the battery. I think the readings are more accurate too.

S.H.A.F.T.
 
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