By Brent Christiansen (152.163.207.48) on Monday, October 22, 2001 - 12:21 pm:

I rebuilt my EK about 5000 miles ago. Had it bored and honed with new pistons and rings, bearing and had the head rebuilt. It has a Weber on it and runs well compared to how it used to run. My problem is that the compression is only 120psi when the motor is warm. I don't remember exactly the break in procedure I did cause I was a long time ago, I don't drive it much because of other problems, but I know I followed the instructions the machine shop gave me to a tee. I also have never run synthetic oil in the motor. I've tried two compression testers and there is only a 5psi difference. Is it possible the rings didn't seat. Is it possible to re-seat them?? Sorry 'bout the long post. Thanks!

By Brent Christiansen (64.12.104.27) on Monday, October 22, 2001 - 01:29 pm:

I should also mention that the Haynes manual for a '79 Prelude stated that the pressure should be 185psi and the minimum is 165psi. I'm pretty sure that this Prelude had EKs in them didn't they? I'm also considering getting a junk yard motor from a '84 prelude and putting it into my '80 accord. They only have two but for $50 for the motor and carbs I'm having a hard time passing it up. What should I look for? It all depends on if the EK is OK or not. Thanks again.

By civic1200freak (65.34.31.195) on Monday, October 22, 2001 - 05:18 pm:

Yo Brent,
Did you double-check your valve clearance? Were you certain which valves were intake's and exhaust's. They can be confusing on cvcc's. Also how many hours and miles of use since the rebuild? Is it broke in enough? How about cam timing? Just some thoughts to throw at ya....Rick

By errol (64.12.107.184) on Monday, October 22, 2001 - 09:29 pm:

Gosh.. There are sooo many things that can happen during break in. I've had a couple of motors that just didn't want to seat. The machineshop ordered cast rings and bored it for molly or the guy wasn't paying attention and honed it just a couple of thou bigger.
But like civic freak said, check the valve lash first, (It's the cheapest) otherwise I'd take the car back to the 'shop' and let them explain....

By ddechon (12.91.126.195) on Tuesday, October 23, 2001 - 02:39 pm:

Don't forget about your gage.

The pressure from your cylinder could be lost in your gage or hose.

The longer your hose or connector is the more volume you are going to add to the cylinder, and you'll also have less compression. Try to have the type of compression gage that measures very close to the engine.

Darrell

By Brent Christiansen (64.12.102.27) on Tuesday, October 23, 2001 - 08:51 pm:

Just to ask the question. What kind of compression are you guys getting? Also, for those of you who have had physics, I used the ideal gas law to figure out if the book was right and came up with 123psi. Am I an idiot? Am I missing something. Also my gauges are the kind you press into the hole and hold there while the motor is cranked, I'm using enough force leveraging my arm on the radiator fans mount to flex them so I don't think I have a seal problem. Also unfourtunately I rebuilt the motor myself and the shop would only be accountable if they honed the cylinders wrong for the type of rings. And last time I adjusted the valve lash I checked it 2 or 3 times per valve to see if I was adjusting the right one. Thanks for all you help I very much appreciate it.

By the way I found a EB3 at the junk yard today. Is it worth holding onto till another rebuild? I was thinking a stroker. They only want fifty bucks.

By Adrian (Civicguru) (203.42.97.227) on Tuesday, October 23, 2001 - 09:06 pm:

Are you checking the compression with the throttle open or closed? You usually check compression at WOT.

Just out of interest, my 13:1 (or thereabouts) motor registered 220psi (couldn't hold one of those silly push on gauges on, there was too much pressure) . The cylinder with a busted piston read about 180 from memory. That was some time ago and that motor is long since dead ...

By Zippy (Zippy) (152.163.197.79) on Wednesday, October 24, 2001 - 08:54 am:

I have a hard time imagining that all 4 cylinders would fail to seat properly yet have very similar compression numbers. Do you have any other symptoms? Have you passed an emmisions test? Poor compression will give bad combustion. I'm inclined to think you don't have a problem. On the other hand, you said you got new pistons. Are they the right pistons? You could have put together a low compression piston/head combo. Also, go over your testing procedures. Testing has a number of vagaries such as engine rpm, throttle postion and gage.

Roger

By Brent Christiansen (64.12.104.53) on Wednesday, October 24, 2001 - 02:28 pm:

I also checked on the cam timing and it appeared to be a tooth advanced. So I moved the cam one gear over to what appeared to be right. My compression is worse. So naturally I moved it back. Then for the heck of it I moved it one more tooth advanced. I rotated the motor with a wrench to see if the valves would stop the pistons and they didn't so I tested the compression again and it came up to 150psi. Just to be safe I put it back to where I started from till I could get some info from the pro's here. Is it even possible that perhaps I got the wrong cam or possibly the wrong flywheel (I replaced it with a brand new one) for this motor. It is also by the way a EK not an EK1 which I'm told doesn't make a difference but I figured I'd put it out there. Anyway thanks for all the good ideas. I've been reading this site for about 1.5 years and have learned alot even though I drive a accord.

By ddechon (12.91.125.206) on Wednesday, October 24, 2001 - 05:11 pm:

Hmmmm

Have you tried what Roger said about the RPM and throttle position? Double check your alignment marks on your engine and timing belt pulleys.

Your flywheel shouldn't be the problem.

Maybe you've got the wrong cam. Try your original cam to see if your readings increase.

Hmmmm
Darrell

By Charles (152.91.9.43) on Wednesday, October 24, 2001 - 05:38 pm:

Leave the cam were you got the highest compression and try running it. What points are you using to line up your cam? Maybe they are the wrong ones. Double check with your engine build manual. If it is a tooth out then you find a marked improvement in performance.

By errol (205.188.199.28) on Wednesday, October 24, 2001 - 10:43 pm:

GRAB THAT EB3 if you can.. (complete! and tranny) Dang, for that much you can't go wrong!

By Brent Christiansen (152.163.201.81) on Friday, October 26, 2001 - 11:29 am:

I'm going to try and set it back to the point where I got the highest reading and maybe try one higher. The only problem is that I don't want to float a valve at higher rpm, which I don't visit to often, and smash a piston into a valve. How far can a cam be off before BANG! Also I unfoutunately can't get the EB3. Not because I can't physically do it but my wife would not appreciate me spending $1000 on it to get it running without trying everything else first, her opinion on the car is teetering and I want it to do well when I get it going again. Could a EB3 move my heavy accord very well? what about mileage? Never saw a old honda motor like that before: manifolds on opposite sides, without auxilary valves, no wonder everone loves them. Anyway thanks for the help.