bigbang

Hello-
I have a completely stock Formula 292 SR1 with twin stock 454 mags. The idles are in sync with throttle levers all the way down. At cruising and higher rpms I'm off maybe 200 rpm from sync, so I adjust accordingly on the levers. What's the method for making adjustments on the throttle cable assemblies? Thanks.

getrdunn

iTrader: (7)

Do you have mechanical indicators or you have the electric senders on the gimbals. Sometimes the gimbal bolts that the drive pivots on behind the tilt Seder can loosen just a tad and throw off the gauge. The senders are adjustable. Also ck gauges vs drive height. Another thing to ck is make sure both throttle plates are open equally at half and wot. Not uncommon to be off a couple hundred. If it bugs you just run with staggered throttles.

When throttles pulled all all the way back doesn't really have anything to do with cable adjustment rather the carb idle screws are just in sync. How many hours on engines? You may be facing that time. If the above doesn't solve your problem I'd say do compression test and leak down. Also ck resistance on both props while in neutral.

Hope this helps a little.

Griff

Are both engines the same rpm at WOT???

bigbang

The drives are even at full in, via mechanical gauges, I have already confirmed that they are equal, and tested rpms in this way. I rarely run WOT, so I notice it primarily in mid-range rpms. Engines are 850hrs. As I adjust one of the throttles to eliminate vibration oscillation between the engines, the tachs agree and are equal. The levers are about half a throttle knob off.

distantthunder

I have a 1989 292 SR1, my levers are one-two clicks off at all rpms, but my grip is quite comfortable with the gap as my middle finger will slide between the gap. This is because the previous owner used two different carburetors and throttle cable brackets so I will be changing those out this year to make everything match.

I would check the distances with a tape measure from the back fiberglass wall to the part where the cable clips to the linkage from idle through WOT. I would also check to make sure your carbs are set up the same. The cables should move evenly but if the carbs are setup different then you will have a drift in performance.

dcb

Where you want to check your indicators is at the trim you are using in mid-range. Differences in cable slack/adjustment can cause the indicators to be off at cruise. Propellers can also be different causing RPM to be uneven. I have not owned a twin engine boat that the throttles were evenly matched all the time.

Griff

One engine might be down on power. The only way to really know is to get a true WOT rpm reading on both engines.

oconnor marine

1. I agree hammer the throttles and look at the tachs! I have a digital synch tach in my 272 and the VDO.
2. Also check the throttle bodies to to see if the are opening all the way when at wide open and see if they are actuating from idle at same time.
3. do a compression test too

bigbang

Okay, thanks for the advice. I'll compare the linkages wot at the carbs. I guess I was wondering if there was an adjustment on the lever end, as I've never dug into the console.

mcollinstn

If you have the Kiekhaeffer Zero Effort levers, then there are adjustable STOPS both ends of travel, there are several holes you can move the cable connector to depending on what throw you need, and there are takeup adjustments as well where the cable end threads onto the cable.
At the motor end, the carb linkage usually has 2 different holes you can use, AND the cable ends are also adjustable from that end.

IF the cables are well-lubed, operate freely, and have no kinks, you can get the levers matched up pretty well.

BUT, you have to MAKE SURE that both carbs are opening up FULLY at WOT, and that both engines are within 20-40 rpm of each other. If they aren't then you need to do some MOTOR diagnostics FIRST.
Lots of boats come from the factory with poorly adjusted throttle cables.

Once you KNOW both motors are within a hair of each other at max rpm, then you can start playing with the linkages. If you cruise more than anything else, then it's a matter of preference WHERE you want the levers to be sync'd with each other. If your favorite is 3,200 rpm, then start adjusting them to get them both in the same "detent" position. THEN if they are off some at WOT, no biggie because they are against the stop. Same at idle, if they are off some there, no big deal.

M