1984 1600 capri and 1984 85 HP force: Clunk under load

[ck85abc3]

When I put a load on the motor by using a lot of throttle, I get a clunk from the engine area. When this happend then engine does a little hop up and then drops back down fast.

Any ideas how to fix this and what is causing it?

I just put on a brand new 15 pitch propeller. With the old mangled propeller it never did this, but then I didn't drive it very much with the mangled propeller.

O ya, I have the leak down problem with my power tilt/trim. Could this be the problem? I wanted to get by the summer without buying a new unit and then pay the winter price this winter.

 

[ck85abc3]

Re: 1984 1600 capri and 1984 85 HP force: Clunk under load

It looks like this is either a shift adjustment problem or worn out gears. I guess I can test this by shifting by hand and seeing if it still does it. Can someone explain how I can shift by hand?

 

[12Footer]

Re: 1984 1600 capri and 1984 85 HP force: Clunk under load

You might have bushing problems. Remove the new prop and check for abnormal wear behind it, and the surface of the shaft housing, or the thrust bearing. It may be that the new prop was not exactly matched for the shaft. Just a guess there. Also, it might be a good idea to pull a lube drain/fill on the L/U and look for water, or chunks of metal in the old lube.

 

[Frank Acampora]

Re: 1984 1600 capri and 1984 85 HP force: Clunk under load

Usually a clunk like that will get worse as speed increases if the drive dogs are bad. If they are really rounded, they will pop out under any load. There is compliance in the shift cable, so: after you shift into forward, with the hood off, reach for the shift lever where the cable is attached. Pull hard forward. this will add a little more travel and if it stops the clunk, then you need to adjust the linkage. The next thing to try is to totally disconnect the cable and pull the linkage by hand. You need to hold it though otherwise it may pop out of gear anyway. If this solves the problem, you definitely need to adjust the linkage. If not, check other areas first, then open up the lower unit and check the drive dogs on the clutch and forward gear.
Sometimes you can get away with reversing the clutch because the reverse dogs don't get as much use and wear. But if the dogs on the forward gear are worn too badly, then you must carefully grind them back to good metal using a Dremel and carbide bits. Takes time but saves almost 300 bucks.

 

[ck85abc3]

Re: 1984 1600 capri and 1984 85 HP force: Clunk under load

Thanks for the replies. I have the clymers manual in the mail...

I'm hoping it is linkage because it came loose by the motor last time I was out and I had to put it back in place and tighten the clamp thingy... if that made any sense.

 

[ck85abc3]

Re: 1984 1600 capri and 1984 85 HP force: Clunk under load

Update: I'm not sure where I was supposed to adjust the linkage, but in the engine compartment I disconnected the linkage and adjusted a bolt so that it would pull more into forward gear. I took the boat out today and it did better, it didn't clunk at low speeds or moderate speeds, but when I was checking top speed I got a clunk. It only clunked after the RPMs got pretty far up there.