Sticky throttle on mercruser

[Timfishin4fun]

Hi all my mate has just bought a 35 ft boat and one of the throttle is really sticky.

The moorings have said the boat has to be slipped, is this true or is there an easy fix.

Thanks

Tim

[shubeej]

tim, the mercruisers have 2 shift cables ,1 which goes from the throttle to carby & 1 goes from carby to gear box in this arrangement there is a set up which has a kill switch that stalls the motor for a split second allowing the gearbox to engage without crunching if you have a look near the carby you will see what i am talking about & you should be able to disconnect these cables & manually try them to se if there is resistance.if it is the shift cable that goes from the carby to the gearbox i'm pretty sure that the leg needs to be removed & hence will have to be slipped.i am no expert but I do have a mercruiser & have had mine replaced before i,m lucky that it is on a trailer.have a look at this link you might get a insight of what needs to be done.http://www.youtube.com/watch?v=wB8rMCQeZyk&p=C226248C493FE29B&index=2&playnext=2 the other thing you might be able to get some lubricant down into the cable from the engine bay might save you a thousand or two
good luck john

[Timfishin4fun]

Thanks mate will give that a go.

Tim

[Fed]

The shift interrupt is to assist in getting the drive out of gear because the dog clutches are undercut, the interrupt system can be repaired/replaced/adjusted from inside the boat.
If you're having problems getting into gear then it will be cables or a gearbox problem.
If it's sticky on the throttle progression then it's probably a cable or controller problem.

[testlab]

Ditto on what Fed said.

I had a 228 M/C and I used to do the leg services myself - beaching a moored Searay onto a cradle during the low and bolting a blanking plate onto the transom mount to keep the water out for a few days was a lot cheaper than slipping and hardstand.

The shift interrupt can be finicky - too loose and it doesn't allow the engine too miss and its impossible to pull it out of gear... too tight and it will stall when passing from F/R to neutral (especially from reverse).

Depending on the boat the shift and throttle cables & linkages are quite accessible if you're fairly nimble. If poorly maintained the fitting on the end of the sheath can grow from corrosion and grip the inner ever more tightly. It builds up and jams sometimes moving one way fully then freezing on the return. Soaking it with WD40 and letting it sit for an hour may help.

Not on my boat, but on others, I have seen the cables routed so they have quite sharp bends and the inner chafes through the outer or it just jams - often meaning you can't reduce speed or disengage gear (but only at the worst possible time).

Disconnect the remote control cable(s) at the engine and then (with suitable leverage) see if the engine/transom linkages move freely. When engaging gears and the engine is not running it may not be possible to get it in gear. This is not a fault and a kick on the starter will allow it slip into gear (first prevent the engine starting for safety).

Regularly lubing the cables can help but a lot of them are sealed tight enough to prevent any significant ingress of oil. I found a regular squirt of WD40/RP7 where inner passes out of outer kept them in top condition.

All of this relates to the older 80s-90s setups.

Good luck.