Valve angle

[sandspur]

After running a compression check I found no compression on 3 of the 4 cyl so I pulled the head & found 2 intake valves stuck open & the others not seating, Are the valve angles 45/45 or 45/30 ?

[67c&ccorv]

45 degree valve seat angle AFAIK.

[MikeB.330]

I thought AFAIK was some sort of strange valve spec until I asked Google...

[67c&ccorv]

I used to think they were quoting the "Aflack" Insurance duck until I looked up the translation in an I-net phrase guide!

[sastanley]

sandspur,

We all like to joke around here, and sometimes we get off-topic. Although I do not have it handy (ON THE BOAT) I think this info is in Moyer's book. If you don't already own it, it is well worth your while to acquire it.

However, here is an alternate source for the info you seek:

http://www.cncphotoalbum.com/atomic4manual/a4manual.htm

one comment - It is uncommon for intake valves to stick - usually it is the exhaust valves

Don't forget when you re-install the head, you need two head gaskets to match the original specs.

[lat 64]

As far as i know

Both intake and exhaust are 45 deg.
Here's a little graphic I drew for ya'll.
In my earlier life, this is how I used to make all three-angle 45 degree valve seats for a 45 deg valve.

We would make the valve or the seat a half degree off to make a nice sharp edge to seat fast and seal tight. The dashed white line shows where this seal would be at first, before it widened with a few million miles. We felt no need to lap these with grit but that was just confidence from lots of experiance. When I was training to grind valves I had to lap all my work to check it for contact all around the seat. I would recommend doing that if you are new to the game.

your smarty-pants motor head,
Russ

[sandspur]

Thank you for the info.
I found 2 atomic 4 manuals on the boat but they are water logged & stuck together with a lot of other books, It doesn't look like any water was in the cyl or the valves, No water in the manifold or exhaust, I think maybe stuck from just sitting, Since I'm this far into it I'm going to do the valves & recheck compression. There was only one head gasket when I pulled the head & it was the new style, I will go back with 2

[sastanley]

First thing I'd try (if you haven't already disassembled the engine, now that we know you are a mechanic!!! ) is to remove the plugs and squirt some Marvel Mystery Oil (referred to as MMO around here) into the plug holes...Turn the engine over with the starter, squirt in a little more and turn it over and let it sit..this usually frees up sticky valves..It seems the moisture in the marine environment can rust up the guides, if I understand correctly.

I have an occasional sticky/not quite 100% valve issue in my #4 cylinder I think. I am trying to get 'regular' about "MMO treatments" in between outings to hopefully free it up and keep it free.

[P30_889]

Check your fuel

As a victim of bad gas I would highly recommend checking your fuel. I had sticking intake valves (also caused by high exhaust back pressure, but my exhaust system is as clean as a carbon whistle) from the goo formed by the bad gas hitting the air on its way to the combustion chamber. It coated my intake and oozed into my carb after less than 1 hour running on my freshly re-built engine. I had treated my fuel with the Stabil (?) but it was still bad gas and really mucked up my system. I emptied out the tank and I am flushing it now hoping to get it cleaned out and usable in the next week or so (Thanks to Mike.B for the fuel pump contraption he was so generous to loan me - it works like a champ)

If you find you have bad gas that has mucked up the valves, it is possible to fix. Not fun but I was able to get the valves unstuck by taking off the manifold and spraying Berkebile 2+2 in the block (toward the valves). I sprayed until the muck that came out didn't look like coffee. (Don't bother with other carb cleaner, the berkebile 2+2 worked after three cans of other types of carb cleaner failed to get the job done.) After getting the gunk out I used MMO in each cylinder and she is running great now (except at idle - but that is another story).

Good luck.

[Jesse Delanoy]

I already owned a Moyer engine manual. When I bought my Moyer replacement engine, it came with another one.

I now have one manual on board, and one at home. I highly recommend this arrangement, and it would be worth the cost of two books even without the replacement engine!