Chris Craft Engine Problem HELP

[jamkar]

We recently overhauled a 283 F and installed it in our 62 Chris Craft. The boat started but is running poorly except at an idle, will not go over 3,000 RPM and this is without a load, backfires through the carb and out the exhaust. Lots of black smoke. This is a new block, new heads, new fuel pump, new carb, new everything. We tried the old fuel pump and old carb and no change. It idles fine, but will not take a load. There is no advance on the old distributer and we are not sure how that works. We have checked firing order (which is no small task on a 283 f), timing, fuel pump pressure, carb, you name it, we have done it, HELP!!!!!!!!!!

 

[SpinnerBait_Nut]

Re: Chris Craft Engine Problem HELP

Welcome to iboats jamkar.
Let's get this up to Mercruiser, Volvo and OMC I/O or Inboard Engine Problems for some answers.

 

[Haut Medoc]

Re: Chris Craft Engine Problem HELP

Welcome to iboats.....
What is a 283 F?......
Backfire through the carb, would mean either lean fuel mixture, incorrect timing, incorrect valve settings, tuliped valve(s)......
The advance is a mechanical one, & the weights are located below the breaker points plate, perhaps they are stuck with rust from sitting.....​

 

[jamkar]

Re: Chris Craft Engine Problem HELP

Thanks for your reply.
The 283 F is a flywheel forward engine, very weird.
Sounds like it might be valves. Our original engine was solid lifters, the new one came with hydraulic. We set them but the engine has not been ran. Will give that one a try.

 

[Buttanic]

Re: Chris Craft Engine Problem HELP

What direction is engine rotation? Be sure the plug wiring firing order is correct for the direction of rotor rotation and crankshaft rotation. CC did some different things back then when they marinized the 283. Did the engine have a timing chain or gear. A gear will reverse rotor rotation direction. As you said somethings are weird. CC may have changed crankshaft rotation from the normal automotive direction which would require a special cam. What new cam did you put in it.

 

[jamkar]

Re: Chris Craft Engine Problem HELP

Everything seems to turn right looking aft. The engine has a timing chain and looks like any 283 except it sits in the boat backwards with the timing chain end hooked up to the tranny. The engine came out of a CC and has the original crank and cam in it. The difference being it is out of a 65 and mine is a 62. I think it might be valves. We went to Hydraulic valves and set them before we fired up the engine and have not set them yet. Do hydraulic valves need to be reset after the engine starts and runs?

 

[jdooner]

Re: Chris Craft Engine Problem HELP

They have to be adjusted with the engine running. Tighten them until they don't clatter, once they're all adjusted give each nut an additional(someone correct me if I don't remember correctly)1/4 turn. Good luck!

 

[Buttanic]

Re: Chris Craft Engine Problem HELP

The valves should not need to be reset if they were done correctly. Did you check the direction of rotation of the distributor. Normal automotive is clockwise. Looking at a picture of a CC flywheel forward the distributor has been moved to the front of the engine. Depending on how the distributor drive gears were configured it is possible that it turns CCW instead of the normal CC. If it turns CCW and you have the plug wires in the CC position that could account for all the backfiring.

 

[cheburashka]

Re: Chris Craft Engine Problem HELP

You've probably already thought of this, but just to check--how's the fuel quality? Are you running it off of an inboard tank? Are you sure there's no water in the fuel? I'd try it with a remote tank first to make sure that fuel quality issues aren't the problem. There could also be exhaust restriction issues. If it runs well at idle but not at higher revs, fuel quality could very well be the issue.

Did you verify that you're getting advance out of the distributor? You should be able to rotate the rotor (I guess it would pivot clockwise on this motor) and have it spring back. Lack of advance could also cause the problems you're having.