We did a compression test today, after pulling FI/ECU fuse off.

Numbers are really low(seems like?). What do they mean and what are possible next steps? Also, if timing is still off, would compression will be low in return or no?
1 2 3 4
50 50 75 40

Thanks again for helping out.

 

When you did the compression test, did you floor the gas pedal?

 

Yes, gas pedal was all the way down to the floor, while we were cranking the car.

Please advise about possible next steps or if I need to redo the compression test?

I didn't do wet test, because readings were really low

 

Guys anyone has any suggestions or advise, please?

 

I'd re-try the test just to be sure - try on a "working" engine as well.

If the numbers are still low - you could try a leakdown test just to confirm......It is sounding like there is some damage - valves bent, ect.

 

Unfortunately, I don't have a working engine

Anyone on the forum has 2001-2005 Civic?

Will compression be low if timing is still off? In terms of damage, will damage be only confined in the 'top' part(cylinder head) or bottom(pistons) too?

 

Your 94 Accord is down as well?

What I meant by tring the compression test on a working engine was some other engine that is running - want to be sure the gauge and testing procedures are being followed.

Timing being way off could impact compression.

Can you remove the VC and spin the engine over with a socket on the crank and watch the valve train - are the valves opening and closing all the way? Is/was there a lot of play in the valve clearance?

Usually the damage is contained to the valves maybe a guide or two. I'd call it rare that the piston gets a hole in it. Again most of the time, pull the head, send it to a machine shop and then put it all back together.

 

Gotcha PM, no 94 is driving like a charm

Yeah, we watched valves when we put the timing belt on by rotating crank clockwise and valves were definitely opening and closing just fine, on both Intake and exhaust side.

Did not check valve clearance, definitely going to check again.

 

So we checked compression on 94 accord only on cylinder 1 and it's nearly ~200, clearly gauge and procedure is right.

We have started pulling the head and now trying to figure out things, should we take the head to machine shop to see if valves are bent/damaged or can see/replace by ourselves?

Any thoughts or inputs would be greatly appreciated.

 

You will want to take the head to a machine shop to mill the head, so it is perfectly flat and seals properly. They can replace any damaged valves.

Another option would be to order a cylinder head that is rebuilt, then you would have to send your old one in as a core.