Okay, I need some advice from some smart guys. My friend has a beautiful late 70's Sleekcraft and I'm afraid if I don't get this thing reliable for him, he's gonna do something crazy like dump it and get a family boat.
Its all stock and a nice clean example of a Sleek. Its all stock with a 454, engine cover, logs, some non-split bowl Berk with a jetovator etc etc. Its a partial stringer boat and could stand to be restored but I'd call it one of the cleaner stock 70's jetboats I've seen. I had it on GPS right at 60 this last weekend at Shasta, just under 5000 RPM's.
Anyway, onto the mechanical stuff. Its got a Holley DP on it and starts and runs well. After a good long run, it wants to load up and die and take about 20 minutes holding the butterflies open to get it to dry out enough to start. I'm thinking too much fuel but I haven't been able to pull a plug and see what they look like. I'm thinking smaller accelerator pumps, maybe going down a size or two on the jets, especially the primaries. Maybe a power valve issue but I only know enough about carbs to be dangerous. Maybe also look at what heat range his plugs are and see if they need to be gapped properly. Could be a fuel pressure problem, maybe too much, could need a regulator?
Other issue is that it runs out of cranking power pretty quickly when it acts up. Its got a Perko switch and 2 batteries. Gauge shows 16 when its charging which seems a little high to me. He claims the batteries/alternator are new and have been replaced. I'm thinking larger gauge, new cable would probably help the cranking issue. I'm sure if many people are firing up 1000 HP beasts regularly, we can find a way to crank up a little 300 HP 454 with 2 batteries.
Now don't ask too many specific questions because my friend isn't real mechanical and I don't have immediate access to the boat.
Any thoughts or suggestions would be appreciated-Aluminum Squirt
Hey AS...
i'm not smart lol...but here goes...what sz is the carb?...may be too big for the motor!...can u try chnging it to a smaller 1?...what kind of fuel pump is it running?...on the batteries...i run the Perko switch also with regular battery cables & have n/p...on the plugs...i run NGK BPR4ES or BPR5ES...alot of people i know run the AC44T plugs with good success...i'm just trying to help with my .02 cents
fastrat
Hey Aluminum,
You say after a good long run it loads up. Does this "loading up" happen as your coming off plane and the boat is settling back in the water? If so your floats are too high and gas is coming out of the vent tubes dumping straight down the carb. Thats an easy fix. Being I'm not a jet boat guy I cant say for sure. But, on I/O's the way these type boats settle down in the water, With the bowq up high for a short time. The float has the be lower thant it would for a car or this will happen. One thing you could try is take a short piece of 3/8 gas line and slip it over the front and back vent tubes with tye wraps. You'll have to cut a slice out of the middle of the hose to allow it to breath. Kind of like cutting off a peice of cheese. Try it, if it dopesn't load you've found the problem. On a car the fuel level is supposed to be just below the screw hole on the side of the bowl. This may be to high for a boat.
AS far as the cranking. I've had this same problem. When mine would flood out I didn't even attempt to start it for about 15 mins. With the carb all the open. Take a meter and check the battery when its running. You should have between 13.8 and 14.4 volts. Don't trust the gauge. If that thing is charging at 16V it will boil the acid out of the battery. Larger battery cables are always a good idea. I make new ones for just about everything I have. I use old welding cable. You might consider pulling the starter and having it rebuilt. Sounds like the windings are breaking down and pulling to many amps. Thus draining the battery. Also ask the person at the starter place if they can double wind the battery. I've had several done like this. And its cheap to do. I've never payed over 100.00 for a starter rebuild. And, also once I've had them rebuilt I've never had to replace them. Stay away from the Auto Parts rebuilt starters.
Hope this helps some, If not to hell with ya
check float levels, but also check the needle valves making sure they're sealing off. i'd want to pull the bowls and make sure everything is real clean, and the gaskets are all in good shape.
can the boat run for a short distance ok? does it load up, or just die? if it just dies, i'd wonder what kind of ignition it has. some ignitions have pieces that will work fine when cool, but then fail open as they get hotter, then work fine again when they cool back down.
i'd echo what was said about having the starter rebuilt. when they're getting pretty well worn out, they tend to draw more amps trying to turn the engine over. a larger cable can carry more amps, but doesn't necessarily address the problem.
Let's make it three.
Nothing to add but that I agree with both the above posts. As I was reading the problem it's exactly what I was thinking.
Floats and or needles, and starter.
I had the same starter issue. Had the starter rebuilt and still had an issue. So I went down and had 1 ga welding cables made for the battery conections. No more problem.
As for the fuel issues I would have to agree with the others here. Floats, Needles, and or pump.
It will not load up after just a short WOT run. It tends to load up after being run hard for a more extended amount of time. It starts to load up when you come off plane as it settles in the water. I was working the throttle pretty good to keep it running and just kept losing ground until it died. I didn't even think about float levels, good idea, thats why I ask around on here. OK, let me start with the simple stuff and look into the carb cleanliness and look into the float level. I'll also suggest a starter rebuild and maybe we'll build some BIG battery cables and make sure his connections are all good.
He is a good friend but maybe I'll make it run worse and he'll sell it to me for nothing :boxed: . Its begging to be blueprinted, full stringers layed in, a split bowl pump, and a few hundred more HP. Are Sleeks solid hulls? Safe at speed? Keep it below ___ MPH? I really like the look of the hull and with the engine cover it would make a great little retro sleeper to play around in. Thanx for the suggestions-Aluminum Squirt
What is your fuel pressure? If your running too high you'll force the needles open and push fuel out the vent tubes as well.
What fuel pump?
Hey Aluminum,
I'm in the process of restoring a 84 Chris Craft bow rider. I'm enjoying it and learning alot. I have had these same kind of problems with mine. Mine turn out to be a little of everything. You mentioned an engine cover. Does it have one now? I removed the small cover on mine. The type that had the small seats next to the engine cover. I have replaced it with a full sundeck on the back. That created a whole new set of problems. It was vapor locking on me. It was running lean, and it also uncovered a weak fuel pump and also a weak coil due to the extra heat. The engine has always run cool but it wasn't getting much airflow at all. Stay with it you'll get er done.
If at all possible throw it in the water and try the fuel hoses like I suggested. Then try to make its mess up. You'll know right then if its the floats and or needle and seat. I bet it is.
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