Repairs in Seattle

[dnadave]

I have a couple of questions about getting Ivy repaired here in Seattle. Ivy is a 1960 25' Chris Craft Custom Cruiser Cavalier with the original 283 V8.

1) What are the appropriate spark plugs to use? Can I just go to the auto parts store, or did CC use some special plugs on these engines?
2) Where is a good place to take my San Juan Engineering heat exchanger to get dipped and checked?
3) I need to have my carburetor tuned. I've had it rebuilt, but I have problems achieving greater than 12-15 knots at WOT. Not that I'm wanting to cruise at greater speeds, but not being able to achieve a greater speed indicates to me that there is a problem with the adjustment on the carburetor. Anyone in Seattle have a recommendation for a good place to have this done?

Thanks!!

Dave H

[2MeterTroll]

Vplugs with the proper gap. sounds to me like you are already having problems in this bit.
get a set of feeler gages and gap your existing plugs. i will bet you get better performance. I would look at the plugs before i even thought of tuning the carbs. i would also look at the timing and set it a touch ahead if i didn't know when last the timing chain was replaced. Only as last resort would i fiddle with the carb.

[Tom Robb]

If you can't find an old-school Chevy engine guy in Seattle, my faith is shattered.

[Lew Barrett]

There are many, many good mechanics for 283 help in town. Any decent auto mechanic can service it. This is a simple, mechanical era package that can be tuned and diagnosed in two hours or less.

How fast you go is less important than how many revs you are reaching under load.

The drill is this:

1. Check all mechanical components, and make sure you have good even compression in all cylinders. Marine conversions can be either hydraulic or solid lifters. You need to know which version and what style of valve train you have to take valve adjustment out of the tuning equation. If solid lifters (which I tend to doubt) you'll need to make sure you valve clearances are adjusted within spec. I'm not sure how many different versions Chris Craft supplied of the 283, but I suspect there were quite a few. The heat exchanger can be checked at a decent radiator shop, or taken to a specialist marine mechanic. If you are running hot, there is a chance the ignition timing is off and/or that you are running lean. But I too would suspect cooling problems first. Do you have good flow out your exhaust? Have you checked all your pumps?

One of the standard recommendations in town for gas motor repairs on the lake is Pat's Marine Engines. Full service, full charge shop.

2. Adjust all ignition components so that your ignition timing, plug gap and all related components are within manufacturer's specification. If your system has standard points and condensor distributor, replace points, rotor, cap and condensor annually. Old marine engines seem to wear their ignition components at a much more rapid rate than road going vehicles. It's probably a combination of "climate" and load. Check your spark plug wires as well as the high tension lead from the coil, and make sure they are in good condition, or replace using an available kit. Cut leads to length and attach using a new distributor cap and rotor.

Plugs should be cleaned, gapped or replaced according to wear. Plugs can be hard to diagnose visually as small flaws in the insulator can produce misleading results but you can try cleaning yours first. If the age and condition of the plugs is unknown, just replace them. Check gap first as previously indicated. It takes a variable out of the equation. Fisheries Supply also now carries engine parts and has the necessary cross reference manuals. They can look up the plugs your specific motor is intended to take. . As I said, if in doubt, replace. Carquest on Lake Union also carries a pretty good range of replacement tuning parts.

Now you can play with the carb. But if you had it recently rebuilt, the only problem should be bad fuel. Is your fuel fresh and known to be clean?

My experience with gas marine engines almost always led me to ignition wear first. If you really suspect your plugs and nothing else, go ahead and replace them. Plugs are cheap enough to take a crack at. But if that doesn't repair it and you have no better ideas, you'll need to go through the process I outlined (very crudely) above. If you still have problems, or simply want to bring a pro into the equation, come on back and I'm sure a few of us will be happy to give you some "standard" recommendations for good boat mechanics.

[J. Jumonville]

Dave,
I have the complete manual, specifications, and parts list for the Model “ 283” Engine. This manual came with my 1961 36’ Chris Craft. The manual is dated September 59.
Spark Plug Champion UJ-6M
Gap .028
Touque Spec. 23 ft. lbs.
Champion no longer list that number but their equivalent plug is Part # RJ6C.
If you need any of this info I will e-mail it to you.

Justin Jumonville

[dnadave]

Justin: Thanks for the part number! Most helpful!

Lew: Helpful as always. I had thought that the carb might be running lean, too, but I found something interesting when I removed the heat exchanger yesterday. There was a plug, not a restrictor, but a solid plug, in the outflow hose. I'm still having the exchanger checked since it is out, but I think I found my heat problem.

Oh, and it is a solid lifter 283. :)

Thanks!!

Dave H

[dnadave]

Heat exchanger is in and new plugs installed, as well.

Here is the installed heat exchanger:
file:///home/david/heat_exchanger.jpg
499

and here is the plug:

500

This plug is about an inch in diameter and completely closed off the outlet from the heat exchanger.

Things are working much better, now!

[Lew Barrett]

A satisfying conclusion! Hooray!