Cloudy Bowl among other things

[matthewmcp777]

This is possibly one of the most amazing forums -- you all have been so very helpful!

Well I've got the spark issue resolved and now I'm moving on to the next issue at hand, getting her started.

While initially cleaning her out I also "removed" the original fuel tanks. This is a 1968 Columbia 36 and I found it very, VERY odd that the fuel tanks seemed to be made of plywood but I kid you not, that's what they were made of. A bottom and side shell of fiberglass and the top was plywood with a resin layer -- anyway - upon discovering this I decided it would probably be a good idea to install a new fuel system all together.

I have my new tank in, new lines, filters the whole nine yards - but while inspecting the engine I made some very curious discoveries.

1) Fuel Pump Bowl -- seems to have some type of sediment in it -- how do I clean this out -- should I worry about the rest of the fuel system in the engine having "sediment" in it.

2) Oil leak -- this one really has me stumped - noticed some oil in the bilge while working on the electrical side of things; traced it back to the flange on the carb -- this doesn't even make sense as to why oil would leak from there or what would cause it to?? Thoughts and ideas please?!?!

3) Compression test - Given the run around I had with the electrical system I want to be sure that everything is good on the compression end of things. I didn't have a way to spray mystery oil in the spark plug holes, but pour a slight amount (quarter of a shot glass perhaps - less - and since we are sailors I know you can measure things in shots :P ) that's been in there for maybe two weeks but there have been numerous occasions where I've cranked the engine. Anyway I was going to put a compression gauge on it, what reading am I looking for?


That's all for now! I know just a small thing to ask - hope all are well and have wind in their sails!

[Marian Claire]

The "oil" you see at the carb to manifold connection could be the oil you put in the cylinders running down the intake ports. That connection has a gasket. You could remove the spark arrestor and see if any oil has pooled in the carb.
Dan S/V Marian Claire

[Marian Claire]

This is part of a post by Don Moyer. 8) Shut the engine down and check the compression as soon as you can remove the spark
plugs without burning your fingers. The combustion chamber volume in the heads of inservice
Atomic 4s vary considerably, and compression can therefore vary from as low as
85 psi to as high as 120 psi, with the average being around 100 psi. Compression
readings should have a maximum spread within 5 or 10 psi.
Found here. http://www.moyermarine.com/forums/at...5&d=1199135053
Dan S/V Marian Claire

[ndutton]

While initially cleaning her out I also "removed" the original fuel tanks. This is a 1968 Columbia 36 and I found it very, VERY odd that the fuel tanks seemed to be made of plywood but I kid you not, that's what they were made of. A bottom and side shell of fiberglass and the top was plywood with a resin layer - - - -

The ethanol blended gasoline will have wreaked havoc with the old fiberglass tank, dissolved it and sent the effluent downstream. Such tank construction was standard for Columbia back in the day.

During my tenure with them (1971) it was no longer the practice with fuel tanks but water tanks were all made that way; a molding in the interior liner that was covered with lined plywood for a lid. I probably did 25 of 'em.

[Sony2000]

I think with the Atomic 4 we can easily accept a differential compression of at least 20 percent. 10 percent is a bit over the top.

[matthewmcp777]

90-95 on all cylinders....now what?

[ndutton]

Spark is reported good (at the correct time?), compression is good so there's only one thing left: fuel. Let's get the fuel system thoroughly cleaned out including the fuel pump and carburetor, new alcohol rated hoses and make sure the choke is closing fully.

Once done she should fire right up.