compression, the head, and the manifold

[JarrettF]

After not being able to get the engine started for weeks on end, and after replacing and cleaning almost everything I can think of, I have come to understand that I am not getting compression: only the first cylinder has enough pressure to blow my thumb off the spark plug hole.

I consulted the good book and I believe my head gasket is blown.

I took off the alternator, the starter, and began unbolting the head. All of the bolt heads rotate, but I'm letting some rust breaker sit on them overnight.

I also took off the manifold and I found that the hole that matches the fwd-most cylinder (#1) is black, and very, very dirty. Back by #4 it looks like it hasn't seen any action in a long time. It is dry, with a reddish chalky corrosion on it. And #3 isn't much better.

Could I have had one efficient cylinder and been running fine?

And what is the name of the plate that is behind the manifold? On the starboard side I have the water jacket side plate, but what is that plate on the port side? Should that come off too? Is it just another access panel?

And even though I did a high pressure flush 10 months ago, when I took the water jacket side plate off today there was a whole mess of mud and gunk back there. Ah, raw water cooling!

I'll post some pics tomorrow. Thanks for your help.

[Don Moyer]

We've heard occasional reports of two cylinder operation, but it's quite unlikely that you were running successfully on one cylinder.

The plate behind the carburetor is the valve cover. It should not be necessary to remove that plate to replace a head gasket.

Don

[JarrettF]

I'm part way through the removal of the head. I got all the nuts off, but I am having trouble getting the head off over the studs, I have clearance, I'm just bot getting an even lift, so I think it's hanging on some of the studs. If it proves to be too much, I'll try to remove the studs - what happens if I break one off in the block? Easy out? Drilling?

Here are some pics, including one of the "tap-tap-pry-pry" mentioned in the shop manual.

AND! I have the dreaded green gasket! More pics tomorrow.

Check out the image of the upside down manifold (front of the engine is on the left of the picture). Why is the front so black and dirty, while the back is so dry and corroded...

[JarrettF]

i included images, but they didn't take.

You can see the images here, from the blog for the boat:

the manifold

and, tap tap pry pry
thanks!

[Don Moyer]

Jarrett,

For starters, as long as one or more studs are hanging up, do not apply excessive force on the other end of the head. It sounds as though you need to do more tapping and oiling of the studs. Put a nut on top of each of the problematic studs and tap them sideways until you can see penetrating oil disappearing into the annular space between the stud and the head. As long as any of the studs refuse to take any penetrating oil into their annular space, you will have almost zero hope of the head sliding vertically off those studs.

In a worst case scenario, you will have to work those stubborn studs loose with a stud removing tool as shown in our online catalog (sorry if this sounds like an infomercial). The rotational forces are frequently more effective in breaking a stud loose from the head than a simple straight-line vertical pull.

In a worst-worst case scenario, a stud will twist off above the head rather than yield (even rotationally). In these cases, we drill an 1/8" pilot hole down to 1/2" or so from the bottom of the head, and then drill a 3/8" hole to the same depth to remove the upper part of the stud. The small length of stud remaining will usually release its hold on the head and still be enough to remove with a vise grip after the head slides off the short stub of stud.

Don

[forcenine]

2 cylinders

Don,
Darnit to heck! Why does Jarrett get to run fine on 2 cylinders and I can't run on 3?
Lisa

[Don Moyer]

Lisa,

I'm afraid to comment. Do you think it could be a guy thing?

Don

[forcenine]

But Don, everyone knows women are the ones with more power.

[superdave474]

I don't know about anyone else, but I'd rather be oblivious than powerful.

[JarrettF]

I finally! got the head off. The screwing on a nut and hitting it with the hammer did as much good as wishing on a star, so I went with the stud puller. Beauty! Only one of them broke off in the block, and I feel pretty confident that I will be able to get it out by drilling or EZ Out (however it's spelled).

It was a damned dirty mess under there. I took some pics, which I will try to attach, of the cylinders. I will take one of the underside of the head tomorrow, but as it looks pretty solid (no corrosion, really) I don't think the head itself has any problems.

#4:
I found that #4 has mud and dirt and grime on it. I am assuming that water flowed back and into #4. This is #4:

Considering the position of the other cylinders, is this a normal position for the valves?

How do the cylinder walls look to your experienced eyes? And should 2 & 3 be down like that if 1 & 4 are up?

Do any of the valves look like they are in the right positions?

#1, #2, & #3:


and here is a good shot of #1 and the rotor. does this look normal?



And last question, I don't have a crank, and they are sold out on the MM catalog, so I fashioned a homemade one with some pipe. Should the engine turn with ease? I put all my muscle/weight into it and the thing would not budge. Is this normal? The engine cranked last time everything was hooked up - do I have to "break" it and then it will spin? How much effort does it take to rotate the engine with a crank?

(Does anyone have a spare crank to sell?)

(A great homemade mod would be a socket-type extension to fit on the crank-plug so non-crank owners could still rotate their engines with a socket set.)

[JarrettF]

I'd also love to know why I can't seem to post pictures - here is a link to a flickr account I made so you can see the pics referred to:

http://www.flickr.com/photos/23411388@N06/

[Don Moyer]

Jarrett,

I would avoid Easy-Out technology like the plague. In this application, you are as risk of breaking off the Easy-Out which will make your life much more difficult.

I recommend you drill an 1/8" pilot hole, then a 1/4" hole, and finally a 5/16" hole. You should then be able to work out the remaining threads with an ice pick and 3/8" machine tap. If the 1/4" hole gets a bit off center and brushes against the threads in the block, you can sometimes take an ice pick and work the remaining sliver of stud out in one piece and have really
nice threads remaining.

It's difficult to predict how cylinder bores will turn out before you hone them, but there is nothing particularly unusual about these bores that would appear as a red flag.

One or more of your valves appear to be stuck open, so it's a little difficult to be sure, but number one could be in its TDC position (both valves closed). If this is the case, the rotor should be pointing directly away from the block. If number one is at its TDC position, then number two would be ready to come up with the exhaust valve closed (it appears to be stuck open) and the intake valve closed, which it appears to be in the process of doing.

Lastly, an engine should be able to be turned with relative ease. It sounds like yours might be seized. By the way, we are on the verge of introducing a 3/4" hex-headed cranking attachment to enable folks to rotate an engine who don't have the space to turn a crank. Check the Ignition section of our online catalog or type number 479 in the search block of the online catalog home page in the next several days.

Don

[JarrettF]

alright, interesting. very interesting.

so if it is seized, is that fatal? How does one go about getting everything moving again. And why would it seize? I have a "full" indication on my oil dipstick.

And with two stuck valves and a leaky head gasket, that would explain low/no compression.

As far as unsticking them, do you recommend I take them out, or is this something I can solve while I'm solving the seized engine?

[David Masury]

As far as things being stuck or sticky at best... here is a tip from a tractor forum that work well for unsticking engine and valves. Either use stariaght ATF (automatic transmission fluid) or ATF mixed with acetone to free up metal parts. I was given a lawn mower that had been run dry of oil... applied ATF to the engine and two days later it turned easily...

Best of luck

David

[Don Moyer]

Very interesting David! I would think that acetone would have the effect of making the ATF thinner for better penetration. Do you have a recommendation on the proportions of acetone and ATF?

Do