I just adjusted the valves in our Sabb G engine and was surprised at how much the gap was out of spec after 58 hours of engine time. The engine manual states the valves should be adjusted every 300 hours or when they begin to tap.
Stan and Jeremy what is your experience regarding valve adjustment vs. engine hours?
Fair Winds,
Rod
BCC IDUNA
Hi Rod,
I think I’ve only adjusted the valves 2-3 times since I’ve had the boat! I don’t recall how far out o tolerance they get. I’ll be down at the boat (still on the hard) this weekend. I have a couple engine projects to get done - including a test firing. The engine has not been run in nearly 3 years. If I remember, I’ll check the valves and se how far out they are. How far out did yours get after 58 hours?
I still have some cooling water plumbing projects to take care of, including the vented loop. I gather you don’t have one Rod - how do you prevent water from flooding your exhaust system after you stop your engine?
Also, how do you stop your engine? Mine stops if I just back the throttle all the way down - I don’t think this is explicitly explained in te manual.
Regards,
Jeremy
Jeremy:
Thanks for the fast reply.
Before I adjusted the engine valves, the intake valve clearance was about 1/8" and the exhaust valve clearance was close to the 0.012" specification. I will test run the engine this morning and check the valves again. Perhaps I did not tighten the locknut on the adjusting screw enough.
IDUNA’s Sabb engine has never had a vented loop in the raw water intake line. The water strainer is above the waterline. The “run” of the raw water intake line is: seacock - strainer - Sabb diaphragm water pump - Sabb exhaust siliencer - exhaust hose - Vetus gooseneck - transom exhaust. The engine exhaust does not have a hot stack, as does your engine.
We stop the engine by opening the compression release per the manual. IDUNA’s engine idles at 400 rpm. Idle specification is between 350 and 400 rpm. If you set the idle below 350 rpm, the engine will stop when the throttle is close. BCC Geta Way Dhow’s engine was setup this way but the manual does not recommend stopping the engine this way. Perhaps this is the reason a raw water vented loop is not specified in the manual.
I need a favor. Our Sabb engine is a G model not a GS feathering prop model but the prop hub is a GS prop hub. If you have time, please photograph Calypso’s GS prop in the fully feathered position and e-mail me a copy.
Thanks and Fair Winds,
Rod
BCC IDUNA
P.S. We are leaving on a two to three week trip on the Chesapeake Sunday 17 July. Our general direction is south but we will “arrange our days around the wind and call the tide our master.” Because of the recent tropical depressions, the weather may become a factor in our plans.
I’ve adjusted or rather checked the adjustment of my Sabb numberous times and rarely found they needed any change. One think you have to be careful of is to securely hold the adjustment screw when tightening the lock nut; there is a tendency for the adjustment screw to tighten itself down as you apply pressure to tighten the lock nut. Double check the clearance after tightening the lock nut.
I have the G model also with the feathering (not the fully-feathering) hub. What is it you are looking for in a picture of the prop in the feathered position?
Jeremy, why haven’t you run the engine in 3 years. You have it in storage? I trust you do turn it over, i.e. rotate the crank every so often?
I’ve adjusted or rather checked the adjustment of my Sabb numberous times and rarely found they needed any change. One think you have to be careful of is to securely hold the adjustment screw when tightening the lock nut; there is a tendency for the adjustment screw to tighten itself down as you apply pressure to tighten the lock nut. Double check the clearance after tightening the lock nut.
I have the G model also with the feathering (not the fully-feathering) hub. What is it you are looking for in a picture of the prop in the feathered position?
Jeremy, why haven’t you run the engine in 3 years. You have it in storage? I trust you do turn it over, i.e. rotate the crank every so often to avoid a flat spot forming?
Hi Stan,
Yes, the boat has been on the hard for 3 years - redoing decks (myself). I test fired this past weekend - fired on the first crank. I did give it a few shots of oil and allowed it a couple hours to wet the rings. Compression seems fine - no discernable leaks when turning it over slowly with the crank. What do you mean bu “flat spot”?
Regards,
Jeremy
Ummm, some old mechanic once told me that an engine will develope a ‘flat spot’ on the crankshaft if left to sit too long. I have no idea if there is any truth to it…maybe just urban legend.
Still, it wouldn’t hurt to trun her over whenever you are down working on her.
Are you installing the teak decks? Or taking them off? Or re-doing the fiberglass decks?
BCC Forums wrote:
I refinished the glcoat deck with Interlux InterthanePlus. The 30 year
old gelcoat was crazing. I ground down the molded nonskid pattern and
replaced it with gritted InterthanePlus.
I won’t get Rod started on teak decks… 
Regards,
Jeremy