FIXED!! No compression in #1 cylinder
 

I just picked up a '97 E350 V10 with 49k miles. It had a miss that I expected to be a COP. Turns out, I've go no compression in the#1 cylinder. Now I'm trying to figure out the next steps. I don't know the history on it but the van must have sat for quite some time as the tires on it have like new tread but are 10 years old. That makes me wonder if I could have a stuck valve, broken spring or a bad lifter, etc. rather than a major failure in the engine. I would love to hear some thoughts/ideas before I dig into this thing too deep.

Thanks!

Ok, I'm getting more befuddled by the hour. Can someone please tell me how I can have absoulutely no compression at times and at other times I get some compression? I can crank the engine for 30 seconds and get zero on the gauge, and other times it kicks the compression. I've had readings of 100 psi, 75, 50 & 20. I reset the gauge and do it again and get nothing. Then I get something. Then nothing again. BTW, it is a brand new compression gauge and I believe that it is working properly. A different gauge has been used that recorded nothing as well.

So, how can I have compression at times and none at other times?

The only thing that makes any sense to me is if I have a valve that is sticking.

Does anyone else have any other ideas??

Ok, I typed a long, detailed discussion of what I've found, but then lost it as I posted it. I'm not going to type it all again. Long and short of it, I found that the rocker arm on the first valve (intake #1, I believe) had fallen off. I presume that a stuck open vavle would have cause that to happen, though the occasional compression and usually no compression still doesn't make sense.

Now the problem is getting the valve cover completely out of the way to re-install the rocker arm. There is not enough clearance on the E350 to take it completely off. If anyone has any ideas on how to do this, PLEASE chime in. I will start that request as a new thread.

Also, if anyone can explain the compression issue, I'd love to hear some ideas.

Next, to get the rocker arm back on and get the valve moving properly and see if there is any other damage.

Cheers all.

Well, so far NO ONE has offered any help on the compression issue on this thread. I have had a considerable amount of much appreciated advise regarding removing the cam cover on the new thread that I started for that. But, as I see that 161 people have READ this thread, at least partially, I'll post the outcome so that HOPEFULLY this information will help someone else avoid the cost of a new engine or a head replacement.

MY ZERO COMPRESSION ISSUE WAS A RESULT OF A ROCKER ARM FALLING OUT THAT RESULTED FROM A STUCK OPEN VALVE!

The following is cut and paste from my other thread covering cam cover removal on an E-series, but most of it is applicable here as well:

Ok. The simple truth is, the cam cover (valve cover) does not come out without either pulling the engine, lifting the body, or MAYBE pulling the intake manifold. I did not try any of these, so I can't say for sure. And, I don't know if one can pull the intake manifold on an E-series without pulling the engine or lifting the body. But, it does look like the cam cover might come off if the intake were out of the way. Even once I got the front edge of the cover over the timing chain, it will only go backward about 4-6" before the hump that covers the timing chain hits the firewall. And, I don't think it could come out forward either. BUT, lucky for me I needed access to the first valve on the front of the head, so that 4-6" was JUST enough for me to do what I needed to do.

And, what I needed to do was re-install the rocker arm (technical name: follower, I think). That I was able to do. And, the result, so far, knock on wood, is that the van is running perfectly now. No miss, no CEL, no vibration, no studder. I had 115 PSI compression with the engine cold. I didn't check it hot. The fact that I had compression was good enough for me at that point.

So again, the conclusion was that when the van was shut off prior to being idled for however long it sat, the intake valve on the #1 cylinder was open. When it was started back up, that valve was stuck. With no valve spring pressure against the rocker arm, it simply fell out. I'm guessing that the valve stayed stuck at least partially open after that, thus no compression. I can't explain how I sometimes got some compression in that cylinder...that part just doesn't make any sense to me. But, it doesn't appear that the valve was damaged, burnt, bent or otherwise by the engine being run with it partially open. Again, knock on wood...time will tell...

Cheers all...I think I earned a beer today!

You've done well Grasshopper---enjoy this: :-partybud & :-drink but responsibly please?!?! :)

It would have been invaluable had photos been taken along your progress BUT in the middle of this I'm sure that's the last thing on your mind. Its still valuable insight into the V10 being serviced in-frame.

Thanks from me---a current 5.4 owner looking for the V10 in a van body too!

Don't feel bad about the no-response.

Very good information on this site but alot of the time responses can take quite a while or need to bump the thread a few times.

Congrats on the repair. These engines are big but thankfully not as big and complex as their oil burner cousins.

Actually JWA, it was Beck's NA...is that responsible enough??

Sorry, I wasn't looking to produce a documentary, lol. And, as I hadn't received a single response, it didn't seem like there was that much interest (until I put "FIXED" in front of the title...that got everyone's attention!).

BTW, I'm selling my E350, 15 passenger, V10, Quigley 4x4 if that interests you.

1997 expidition 4.6l compression issues