Twin engine torque steer
 

I have twin 454s with bravo 1s. The steering alway pulls to left...hard, when I am planing and trying to go straight. Have the standard bravo power steering. Is this a tie bar setup issue? Maybe normal? Any advise would be appreciated.

BT :cool:

hi bt,
hows it going. sorry we haven't been able to hook up for a beer but i haven't been in the water since i broke the upper gearset on the bravo. the big boat has had no better luck.
any way, have you tried to check your drives by holding a 2' square off your transom to your skegs to see if one of your drives isn't way out ? hope it's an easy fix.

Fran

Not normal.

Are you sure that you're running counterrotating props?

Sounds to me like your not counter rotating the props. A tie bar will make everything stronger but will not effect your problem. If the drives are not paralell the boat will still go in a straight line. Both drives will be angled slightly out from straight. The thrust line will still be straight forward but not very efficient. With both props turning the same way the back of the boat will walk to the side under power- more noticable when getting on plane.

I have bravo 1s and they are counter rotating. I had both props reconditioned recently, so the pitch is consistent between them. Torque steer may not be the correct term. It pulls to the left somewhat when on plane. Nothing bad, just not accustom to this. Thought maybe I had too much toe out or in on the tie bars. Any more thoughts?

Hi Fran... well get that brewski yet. Let me know when you are running again.

BT :cool:

Would you guys say it is normal to be able to let go of the steering wheel for a short moment while planing, and still have the boat go straight. Mine will meke a wide left turn if I do that. My last boat was a single with a duo prop. I took that on long (70 mile) cruises. I wouldn't hardly touch the wheel... did most the steering with the trim tabs. Made it easier to follow the lines on the Loran.

Thoughts?

Excal... how did the transom problem turn out? Don't you have 2 boats?

BT :cool:

As long as the props have the same pitch and the engines are turning the same rpm the boat should go in a straight line as long as nothing like wind or waves acts on it.

Thanks tink... I'll play with the outdrive trims a little more to see if that makes a difference. Maybe I need to put some of those stupid little zinc tabs on the outdrive?

BT :cool:

bt, i do have two boats. the upper drive broke the gears on the bravo. ( little boat) it may have ruined everthing in the upper. i'll have to check the tower to see if it cracked but the pinion gear is stuck so i can't tell yet. i just bought US fountain 1's upper.that should be together next week.
the big boat had a stuck exhaust valve wide open on #1 cylinder. took it apart and found a little powerdy rust inside the cast iron guide holding the valve open. that cause reversion. the same happened to # 8 earlier. except that stuck closed and wore off a lobe. neither valve was bent though. then the exhaust manifold risers were leaking on the new emi thunders. the surface of on manifold was not close to flat causing water to leak back into the engine. the hard part is finding the problems. i wouldn't have guessed new manifolds would leak but they did. now that engine has all the bugs of water out but the timing is acting weird when the distributor is tightened. like the cam is walking but its not a roller cam and the taper of the bearings should keep it in place. i posted a question a couple days ago but no one answered it about the timing. i will put some marking compund on the gears of the distributor and look at the pattern and go from there i guess.:rolleyes:

It could also be the p.s. control valve inside the boat. If you can...start both engines on the trailer... bring them up to 2000 or 2500 and see if the wheel still wants to turn. No need to put it in gear since the props aren't pushing anything anyway. Also turn wheel to the right and to the left... any greater effort required one way or the other.This system is similar to 50,s and early 60's GM. With a bad or maladjusted valve you could jack up the car...start the engine and watch the front tires left or right by themselves.

Check your drive and trim indicators with the boat on the trailer. Make sure that when the indicators indicate both sides even that they are actually even.

Cig1... My trim pumps pump at a totally different rate. I'm dicking with that all the time to get engines synced with even trim. Thats what I was going to fact find more about this weekend. See if by trimming while on plane I can make it pull right with the od trim.

Mopwer... that's where I think the prob is... steering servo valve. No experience with this though. I like you suggestion and will try on land. Do you think I need to start both motors being only one runs the PS pump? Thanks for the great idea!

Excal... Hope the vertical shaft is ok. Sounds like US1 pretty much ripped off the lower. The rest of your luck sounds right up there with Jay13's. That sucks big time! Have you been able to go out at all this summer? I never saw your ignition post. I'm gonna go have a peak around the old posts now. Please stay in touch... my boat, after blowing the 2nd motor on Memorial Day is running sweet right now. Not that fast... maybe 70ish.. but running well. I'll pick you up somewhere if in need of a bay fix and we can do the brew!

BT :cool:

TB, Yeah, I don't know what I was thinking...just run the engine with the ps pump. Generally with c.r. twin you don't get any torque steer and don't need the tabs on the outdrive. I never really looked at mine close , but just quickly , it looks just like the old GM valve. On the end of the valve there is a cap pressed in( sticks out like a miniature freeze plug that's in backwards). Behind it is an adjustment screw that you set for neutral steering. Go one way or the other too much and so will your wheel.:rolleyes:

Sweet MO... I bet that is it. I'll let you know what I find.

BT :cool:

yep bt, 2 boats, 1 ride this year. one broken bravo.:rolleyes: i may take you up on the boat ride before i forget where the water is.:D

You know how to PM. Wife will be burning out soon, so I'll be lookin for non-wife stuff to do. Don't tell her... but that is when the fun starts :D Definately drop a line if you need any wrench hands or a tag boat on a sea trial, or anything like that.

BT :cool: