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FiremansMC
07-03-2007, 01:45 PM
I have a 1990 MasterCraft TriStar 190 with the 351. It has the 4 bbl.
Holley setup. The boat runs fine to about mid throttle(35mph) without a skier. If you try and take off fast from a stop or accelorate from mid throttle to full throttle all at once, the thing wants to fall flat on its face. We are thinking it is when the second set of bbl's are trying to open up. We have done everything we can think of. Fresh tune up,(plugs, wires, cap, rotor, etc...), rebuilt the carb twice and double checked everything a third time, new fuel pump, new fuel filters, fuel lines all look good, pickup tube is clean, screens in the brass fitting is clean, gas and tank look clean, and the timing is right on. Is that anything else anyone can think of?

WilliM1940
07-03-2007, 01:54 PM
Carbeurator overhaul. Get a Renew kit and a Holley tech book. Sounds most like the accelerator pump is shot or misadjusted. But if yours has never been gone over, its time.

Danimal
07-03-2007, 02:03 PM
I am having similar issues but not as bad as yours. I have a little bit of a throttle lag when gettin on it. It stumbles a little but it doesn't fall flat on it's face. I will be trying the rebuild kit myself. I also did all of the tune up things you mentioned also.

FiremansMC
07-03-2007, 02:17 PM
I forgot to list this. We have rebuilt the carb. 2 times.

Thrall
07-03-2007, 06:18 PM
My 2 top suggestions were going to be accel pump or timing, but you seemd to have eliminated those problems (as long as the accel pump was reinstalled correctly, I believe there's a spring under the plunger, but haven't pulled apart a Holley since hi school).
Your ignition is vacuum advance, correct? That may be the problem, ign timing not advancing properly w/ rpms/load.

FiremansMC
07-05-2007, 12:28 PM
That is what we think we found. The vacuum advance springs are stretched out. They don't pickup intill half throw so that is my half throttle. Then it can't advance for the second half of the throttle. Still looking to get new springs or a distributor by this weekend. I will let you know if this is what takes care of it. Thank you.

AZDave
07-12-2007, 09:36 PM
I ran into that with my 93 351 Holley.. All advice pointed towards rebuild, but cap/rotor replacement and tightening carb manifold bolts and screws fixed it. You have done everything it sounds like. If the manifold and spacer gaskets are good, you may have to give up on that carb, or at least have Holley rebuild it for you.

FiremansMC
07-25-2007, 12:12 PM
Had the boat on the lake for a couple weeks. Put a different carb on, Edelbrock 650, make it worse. Put the old one back on, got better. Took the boat out on the water and played with the distributor advance. Timing is suppose to me 6 deg. with a tan cap. We now have ours at 30 deg. We are ordering a new distributor and going from there.
Thanks to all

jwchapman
07-25-2007, 01:43 PM
Just a thought - have you put in the electronic ignition to get rid of the points? I did this along with a new cap and rotor (plus the plugs and wires you already did) on my 88 TriStar (351W) 5 years ago and it helped across the board - from easy starting to full throttle from any point in the power band. This is the best $100 I've spent on the boat. I can not overstate how much better it made the boat run. If you haven't done this you might want to try it before buying a whole new distributor.

Also - do you know which carb you have? When I bought mine, a previous owner had put a 4160 on the boat - I have not touched it. I have read the 4110s are much less reliable and almost impossible to tune or even rebuild - though I don't have any experience with them. Good luck - John

TRBenj
07-25-2007, 02:16 PM
Just a thought - have you put in the electronic ignition to get rid of the points? I did this along with a new cap and rotor (plus the plugs and wires you already did) on my 88 TriStar (351W) 5 years ago and it helped across the board - from easy starting to full throttle from any point in the power band. This is the best $100 I've spent on the boat. I can not overstate how much better it made the boat run. If you haven't done this you might want to try it before buying a whole new distributor.

Its not exactly clear what the OP was talking about regarding his distributor, but if the timing isnt advancing properly, then an EI kit wont do a bit of good. Initial timing should be somewhere between 6-10 degrees. Final should be somewhere around 30-35 degrees, and should be fully advanced by 3k RPM.