Pulled off the head, need advice on next steps

[theredboat]

Hi All,

It took about a week of spray-spray tap-tap, but I finally got my head off in order to replace it with a used head I got from MM.

I'm not an experienced mechanic so I'm looking for some feedback on these images I took.

1. It looks to me like the valve on cyl 3 is stuck in the closed position. How do I open that?

2. Whats the best/safest way to remove all the gunk from the head and inside the cylinders. Most of this is gasket material from prying up the head.

3. The studs you see in their posts....Can i just keep these in when I put the new head on? The ones that came out are studs that got removed along with their nuts. I'm going to replace these.

4. It appears that there is some stuff stuck down inside the valve of cyl 1. Any way to get at that stuff without removing the valves?

[lat 64]

Did you mean to say the valve is stuck closed? Usually the valves stick open and the spring can't close it.
If your valve is stuck in the closed position, then somethings really broken down in the camshaft. Can you turn the motor over with a hand crank and watch the valves to see if they move up.
Gentle scraping and a shop vac to suck up the goo from that mess. Don't scrape in to the base metal; cast iron is soft compared to paint knifes and scraper blades.
Get it clean enough to eat off of and you will be close.

Russ

[sastanley]

Hi trb,

You need to clean everything. Do not under any circumstances put the motor back together with all that gunk in there.

I know you don't want to hear that, but it is my strong opinion that you clean it up. You can likely use a shop vac to get the loose chunks, and then even use a hose & soapy water...there is nothing wrong with doing that to a metal block...as long as you thoroughly dry it (grab the wife's hairdryer!!) & don't store it wet or with bare metal exposed to the atmosphere. Maybe a nice light coating of MMO would be good too so that moisture doesn't damage exposed metal before re-assembly or wrap it in oil soaked bath towels, etc.

[Kelly]

Studs

Red,

When pulling the head off my A4, several studs remained in place. I left them where they were and had no trouble reassembling and torquing the nuts as per the Moyer manual instructions.

Be sure to clean out all those cooling water passages as the others have stressed. I'm assuming a saltwater cooled engine here. Might I suggest the fresh water cooling upgrade? My FWC engine was MUCH cleaner when I opened it up. This is what it looked like when I pulled the head. You can still see pieces of the old gasket (notice the studs I left in place):

[Kelly]

...and the head

Here is another picture just for comparison:

[Seabee Chief]

Been there!

Hi trb,
Having been there a couple months ago, I totally agree with the recent threads. After diagoising the blown head gasket we decided we needed to remove the head. I also cannot over stress the importance of cleaning EVERYTHING! DO NOT RE-ASSEMBLE the head without cleaning everything. We used engine cleaner, scrapers, water spray gun and anything we could to punch out the waterjackets. All the water jackets need to be flushed out in the block and also the head. Don't forget the thermostat. I just cleaned mine, tested it and put it back. You can replace it if you think you need to. Prior to removing the head, mine was so clogged that my temp sensor was giving us a false reading. After a good cleaning it work great! I also left my studs in the block against the MM Overhaul & Repair recommendation and everything torqued up fine. Be sure the threads are clean so up get an accurate torque setting. Chase them if necessary. Be sure to use the two gaskets supplied by MM. Remember clean is key.
Good luck,

Chief

[dthibaul]

Studs

One minor suggestion I would make subject to the disagreement of others. Since you have gone this far, I'd replace all of the remaining studs (if you can remove them w/o breaking them). The studs that did come out-what did the lower threads look like? Diminished or missing? Studs nuts/bolts/washers are inexpensive. I like to replace them when I can (and bundle them into the same shipping charge from MM).

[dvd]

Yikes, I Hope mine doesnt look like that. I think now that you have it apart you need to spend alot of time completely cleaning it up. Also, its good advice to try and turn over the engine and make sure the valves are opening. As mentioned if one of them is stuck closed it probably means something is wrong with the cam lobes or possibly a broken cam? If the valves are opending then you must spend time of just cleaning everything. If you can get the studs out WITHOUT breaking them it would be great. Good luck on it,

dvd

[Al Schober]

At this point in the disassembly, I'd remove ALL the valves, clean them, inspect them, and have them ground in a shop if at all doubtful. Not expensive.
Then I'd use valve grinding compound and lap them into their seats in the block. A shop would use the proper tools to contour the valve seats and control their width. I've never felt it necessary to have this done, or to buy the tools to do it. To see what would be required, do a Google on Goodson Tools - browsing their catalog is an education by itself!

Al

[theredboat]

getting there

thanks so much for all the advice!

well, ive done quite a bit of cleaning. wondering how much more i have left. This is about a days worth...

There are some pieces of gasket still left, though it seems to be incredibly thin. Plastic scaper doesnt get it of, nor does a soft wire brush. im worried that I may damage the surface by chiseling it.

Also, a strange (bad?) thing happened as I was cleaning around one of the valves. It sprang closed. You can see it in the picture. Both the first cyl valves are close and the second cyl valves. Will it pop back up next time I crank the the engine? Not sure how to proceed. I dont have the hand crank.

I did remove the plate under the manifold to inspect the valves, everything looked OK with the exception of one of the springs which looked slightly damaged.

[hanleyclifford]

The "springing" closed of the valve is a good thing. It was stuck open. Before you go any further prepare a wooden block with individual holes so that as you disassemble, each valve and its related parts can later go back exactly where it came from. You can complete the cleaning of the block surface with a single edge razor blade or similar tool.

[rigspelt]

Interesting puzzle for a non-mechanic like me to try to work out over a morning coffee: A hand crank would be the slickest way to see how the valves are working in that engine I suppose, but let me try a prediction based on logic.

I made the attached drawings when I was trying to figure out how an A4 works, and then used them to label your original photo, presuming exhaust valves are smaller than intake valves (I see the distributor in the background, which is how I numbered them). I think I got them right. Ref: http://www.moyermarine.com/forums/showthread.php?t=2927

Russ and Hanley confirmed that valves usually stick open. In your original post, the open valves were E1, E3 and I4, if I figured this out right. On cleaning, the #1 exhaust valve snapped shut, as if it had been stuck open maybe?

If I remember my self-taught mechanics right, 4-stroke engine cylinder's four strokes are (http://www.moyermarine.com/forums/sh...92&postcount=6) Compression, power (fires), exhaust, intake:

Up - compression, both valves closed
Down - power, both valves closed
Up - exhaust, exhaust valve open
Down - intake, intake valve open

The A4 fires 1-2-4-3, which means the following situation at an instant in time when #1 is in its power stroke:

1 - power, is firing now, both valves closed.
2 - compression, so will fire next (compression, power), both valves closed.
4 - intake, so will fire after #2 (intake, compression, power), intake valve open.
3 - exhaust since just fired, so will fire after #4 (exhaust, intake, compression, power), exhaust valve open.

This is the situation now for that engine, if that first valve had simply been stuck open:

E1 closed
I1 closed
So #1 is in its power stroke and is firing (power).

I2 closed
E2 closed
So #2 is in its compression stroke and will fire next after #1 (compression, power).

E3 open
I3 closed
So #3 is in its exhaust stroke and will fire after #4 (exhaust, intake, compression, power).

I4 open
E4 closed
So #4 is in its intake stroke and will fire after #2 (intake, compression, power).

So, if I have all this right, here is my prediction for that engine now:
1 - power, both valves closed, and the piston should be on its way down.
2 - compression, both valves closed, and the piston should be on its way up.
3 - exhaust, E3 open, and the piston should be on its way up.
4 - intake, I4 open, and the piston should be on its way down.

Right??? Your photo of the pistons here here seems consistent with my guesswork.
---

[hanleyclifford]

Rigspelt - After that incredible detailed analysis you should stop calling yourself a "non" mechanic. Truly impressive and useful for this issue. Your discussion reinforces the requirement for care and orderliness as disassembly proceeds. Next we should see a picture of the valves, in order, before cleaning begins. After that the valves can be cleaned on bench wire brush. Then another picture, clean valves in order. After that, calipers on the stems...but let's not get too far ahead of ourselves. Regards, Hanley

[alberg]

Just logged in after a long summer. Looking at the photo,s and I would recomend replacing all of the studs as the threads look very thin. Also for me after seeing the extent I would pull the engine and do a complete rebuild. Doing half a job may be a diservise to a good old engine.

John
Alberg30

[theredboat]

Interesting puzzle for a non-mechanic like me to try to work out over a morning coffee: A hand crank would be the slickest way to see how the valves are working in that engine I suppose, but let me try a prediction based on logic.
---

Wow, thanks a lot for that! Very kind of you to take the time out to show me what you've already learned. It's all making sense now.

... Now the debate begins. Clean up as much as possible, replace a few studs, pack up and still get a month of sailing? Or Haul the engine?

Eh... There's always next year for the engine haul out! I need to sail!