Head Gasket Replacement

[Tom B]

My Atomic 4 is presently a very nice Atomic 2. I suspect either stuck exhaust valves in cylinders 1 & 2 or a blown head gasket between them as there is no compression. I will be taking a shot with some Marvel Mystery Oil to cure the possible sticking valve problem, but suspect the next step of pulling the head will be necessary.

I know that I will be needing new head gaskets. But on review of the overhaul manual noticed that other parts may also need to come off, requiring additional gaskets (the exhaust manifold for example).

For this sort of head gasket replacement, what additional parts are needed.

Thanks.

Tom B
SV Jubilee
C&C 35 MKI

[Tom B]

Atomic 2 update

Well the Marvel oil was a bust. It sure is amazing though how well she runs on two cylinders.

A little background may be helpful. We bought Jubilee last year at a boyscout auction. We started out looking for a daysailer an ended up with a 35 footer. We got her for a great price (less than 1/2 the survey value) but she is for sure a much bigger hole in the water that we had been planning on. We love her and she is a fine vessel and will serve us well...if I can just get her shipshape.

I used a mechanic to get her running after realizing that I might be over my head...but after what he charged, I am now concerned that I may be getting in over my wallet. I have not worked on engines for about 45 years or so. Although my understanding of the concepts is fine, my confidence level is nil. I also find it hard to justify getting a bunch of expensive specialized tool to use once if they would end up costing more than having someone else do it for me. But I digress...

As I said, we got Jubilee in Tacoma at the auction...She pretty much sat idle for the last 10 years as near as I can tell. She was driven to the Tacoma auction site from Lake Washington (~25 NM). During the delivery she blew a water hose and got so hot the paint was burnt off the engine in many places, including the head. This supports my suspicion that the head may have warped enough under the heat to blow out the gasket or worse.

She ran OK for a while. At least well enough to get her out a few times and bring her from Tacoma to her home port here on Vashon Island...but it may well have been on 2 cylinders. All I can really say is she started and ran...until last month. The she would start, run for about 30 seconds and die. I hired a local mechanic to get her running again. Which he did but in the process we learned of the dead cylinders.

Today I put Marvel Oil in 1 & 2, turned her over a few times, put in a little more, turned her over some more, put in more, then started her up. Lots of smoke for the initial few minutes..but still seemed that 1 & 2 were not in play (I confirmed this by taking off the plug wire on each with no perceptible change in engine sound). There is a clicking sound in the engine that seems to be near #2 cylinder.

To add insult to injury, I also noticed exhaust smoke in the aft bilge coming out from the cockpit lockers. It is not in the engine compartment or in the port locker where the water exhaust stack it where the waste water goes back into the system...but apparently in the bilge area between the aft wall of the engine compartment and where the exhaust pipe goes out to the water recovery stack area in the port locker. I guess will need to climb down into the STBD cockpit locker to get a better look at things tomorrow. (On the C&C 35 MKI the port locker is small to allow for the 1/4 birth but the STBD one is big and deep enough to get into to see under the cockpit).

I am considering taking a shot at pulling the head myself. I have noticed that the engine compartment is getting bigger, the more time I spend in there. But I am concerned that I could end p doing more damage than good if I do it myself. Taking off the carb and exhaust manifold and to pull the head and taking out the studs as described in the manual all makes me very apprehensive.

Any thoughts,cautions or encouragement will be greatly appreciated.

Tom B
SV Jubilee
C&C 35 MKI
Vashon Island WA

[Dave Neptune]

Do it yer'self

Tom, if you had any experience at all AND you know whicic end of a wrench or screwdriver is which, with the info and helpful attitude of those who play on this site---NO PROBLEM!!!!!!!!!! Just go slowly and take pictures to create a disassembly trail for reassembling or posting here for others to evaluate and assist in your adventure!! One good thing is that if you ever have any problems after working on the A-4 you will be able to probably get her running again without much problem and can take the family to dinner or a cruise with the savings. The more you know about your vessel the safer you will be. Suggestion---Go slowly, take pictures, and get one of Don's manuals.

Start soaking the head "studs" with penetrating oil or liquid wrench then have a beer, clean something and go home to let them soak for a day or 3. Get a good socket and start removing the nuts that come off easy. The ones that don't want to come loose soak again! Then get a smaller socket that will fit over the stud and sit on (not over) the nut and give it a couple of smacks with a hammer and try again. At this point do not worry about the studs coming out with the nuts as you can reset them later.

The head will come off without removing the manifold or thermostat although with the manifold out of the way it may be easier to work around.

This isn't rocket-science just go slowly and take pictures and stuff a few old rags around the motor to catch dropped tools and or parts so you don't have to dig them out of the bilge. Also get a good strong magnet on a stick for parts fishing. If you have had any experience at all you can do it. You may create a little curiosity with other home mechanics on the dock so keep some cold ones around and you may extract some valuable experience, information and even some help for a cold one!

FYI- if you get a small flashlight and shine it into the cylinder through the sparkplug hole you can see the edges of the valves, check and see if they are moving. You also can't hardly hurt these motors by overheating them a bit they are amazingly sturdy with a "HI-nickel" block and forged steel crank.

Once you have it back together you can easily look for the exhaust leak. The exhaust is a P I A to get to in some cases but very simple to work on--another dun't worry!

This site will get you through it!!!
Dave Neptune

[roadnsky]

Tom-
I second the great advice from Dave!
This is a wonderful community with good advice readily offered as well as the top notch support from Moyer Marine.

There is no better feeling than the confidence of learning your iron sail AND knowing that the work is done right.
No one will give your A4 the TLC and attention that you will.

Fill a thermos or ice chest and jump in!

[Tom B]

Jumped in....

OK...you guys talked me into it...the part about knowing the engine was probably the part that put me over the top.

I am soaking the bolts after removing the old broken heat exchanger (I already have the aftermarket Moyer heat exchanger to put on when I am done.)

Will there be coolant in the head and should it be drained before I start to disassemble? I am assuming that the lower coolant hose will do this if I lower it below the head level..

Also, is getting the head magnafluxed and milled once it's off essential, or just silly not to since it's off anyway?

thx

[Dave Neptune]

Go Tom

Yes drain what you can out.

Have the head checked however if it does not appear to be out of flat IE it is ok don't bother milling! And yes the A-4 does use two gaskets on the head!

If you are planning on taking off the manifold you may have it boiled out unless it is in good condition from using coolant.

You will find out how much the "kiss" rule applies to the A-4!

Good luck David

[Dana Mace]

[QUOTE=Tom B;13668]OK...you guys talked me into it...the part about knowing the engine was probably the part that put me over the top.

I am soaking the bolts after removing the old broken heat exchanger (I already have the aftermarket Moyer heat exchanger to put on when I am done.)

Will there be coolant in the head and should it be drained before I start to disassemble? I am assuming that the lower coolant hose will do this if I lower it below the head level..

Also, is getting the head magnafluxed and milled once it's off essential, or just silly not to since it's off anyway?

thx[/QUOTE
I cant believe the room you have
that will save a lot of time.
Good luck
Dana

[Dave Neptune]

Do-it-yerself'

Go Dana!!!!!!!!!!!!
David

[Tom B]

[/QUOTE
I cant believe the room you have
that will save a lot of time.
Good luck
Dana[/QUOTE]

The first time I stuck my head in there it seemed impossibly tight...but the more I get in there the more roomy it seems to be getting. Pulling out the heat exchanger made a significant difference on the port side as well.

Packing to head over the take a shot at pulling the head in a bit. The corrosion on the head bolts and stud ends is significant. So a l;ittle wire brushing is probably in order before applying the socket. The replacement of the studs and re threading them and the head it a bit daunting...but I will just have to take things one step at a time.

I should have new pics later today...wish me luck!

[rigspelt]

Any thoughts,cautions or encouragement will be greatly appreciated.

After hanging out here this past year since I got my first A4, I'm starting to recognize this as the sign of a good A4 DIYr - a diamond in the rough. I can offer tons of encouragement. My only suggestion at present is keep poking away and bring any questions you may have to this forum. After a while, it starts to make sense.

[Mark S]

Tom,

Don't worry about not having worked on engines in 45 years. The A4 is just like the engines you grew up on -- really simple, and it has four fewer cylinders!

Mark S

[P30_889]

Hope it went well yesterday!

I have to say that after all my initial trepidation on working on the engine, it hasn't been as bad as I thought. I am still muddling my way through after pulling then reinstalling the engine. The first 'major' thing I did was to remove the head from an engine with really bad corrosion. It wasn't as bad as I thought. I broke one stud (machine shop fixed that) but otherwise, very straight forward.

[Tom B]

Good Head

I got it off...took longer than I has hoped but the head finally came off. The good news is the there was a suck valve exhaust in #1 which, after tapping it down (harder to tap down than expected), seems to be working fine. There was also some evidence of blow by between #1 and #2 even though the gasket was still there...but some light burning in the head and block in the gap.

Most of the head nuts came off, a few with the stud attached. The villain of the drama was the one stud from the thermostat, which has light rust on it and did not want to let the head off. The hero was the shorty slotted screwdriver that was small enough to fit on the back side of the engine and allow for wedging in with the hammer. It took a lot of wiggle and liquid wrench to get the head off...but we got it.

The head looks flat and no visible warp showed when I laid a straight edge on it. The water passages were a little gunky, but not real bad. I am thinking I should get the head boiled out. And since I have to replace the exhaust pipe as well, I should probably pull off the exhaust manifold and get that boiled out as well.

High def photos on my flicker site if anyone wants to take a closer look at the straight edge on the head and other shots.

I am not sure how to proceed with the head studs that are in the block or the ones that came out with the nuts attached...pull all the studs? How? And how do I get the nuts off the other studs that came off with the nuts w/o damaging the studs?

I am planning on using the flushing kit I got from Don after it is resembled to flush out the block and also change out the oil, in case any crap got in it during the process.

Anything else you guys think I should be looking at while I have the head off?

[Flagman101]

Look for cracks.
When i did my engine my head had a crack that was not visible until i sandblasted it.
On the thermostat side ou the head. And near the altenator bracket. Airline cracks. But once i pressure tested it, they became very obvious.
It looks like the casting mold was misplaced during pouring and end up with a very thin wall.

[67c&ccorv]

I am not sure how to proceed with the head studs that are in the block or the ones that came out with the nuts attached...pull all the studs? How? And how do I get the nuts off the other studs that came off with the nuts w/o damaging the studs?

Anything else you guys think I should be looking at while I have the head off?

Use plenty of rust pentrating fluid and gently heat the area of the block around the base of the stud. (Note - I said "gently"!)

If you don't have a stud puller then use the "double nut" method to unscrew the stud using two nuts that you tighten together and then apply a wrench to the bottom of the two to unscrew the stud.

Use a gentle but firm force and try to "feel" the stud as it unscrews out of the block - you don't want to break the thing in the block as that will make your job a nightmare.

Check the condition of the threads once the stud is pulled - I would run a bottoming tap into the holes and a die over the studs if reusing them. Don't forget to use plenty of cutting fluid while dressing them out. If the threads are suspect after this you may have to use one of the many methods to recut new threads - Moyer would the ones to talk to in this case. My preference would be to use new S/S studs and nuts and washers - they are not as expensive as one would think.

YOU will have to decide how far you want to go on this rebuild - just the head? Or do we go all the way? It all depends on how much money and time you have on your hands. It is your decision.

Good luck!