SB

Could be. Btw:What kind of carburetor ? Quadrabog or Webber ? Edit: I just saw year, 89, so Prob quadrajet unless replaced over the years.

Brad Christy

SB,

Holley 750 Marine. Don't remember the exact model, but it has the jet plates instead of thread-in jets, if that helps.

Thanks. Brad.
(937)545-8991

SB

If new issue, Two likely areas are the red silicone nipple under the acc pump diaphragm and the needle and it’s area under the pump squirter.

Griff

It has a plates for the primaries and secondaries?? The only time I've seen a plate is used, it was for the secondaries on a vacuum advance carb and that would make it a 4160

Brad Christy

Griff,

It very well could be. That sounds about right, as far as the jet plate goes. I bought the carb several years ago, probably '12 or '13, and haven't even thought about it since getting it dialed in initially. It was a "new" used unit from Ebay. It had supposedly been mounted but never primed. I remember it didn't smell like gas when we unpacked it. But it's been many moons since then. I'll ask.

Thanks. Brad.
(937)545-8991

TomZ

Just now reading, I didn't think it was the fuel pump. 4.5 lbs of pressure is more than enough for a mild 454. If it ran good last year, and has issues now, suspect ethanol deposits unless it was run with ethanol free religiously. Probably has some trash in it.

Brad Christy

TomZ,

Too late. 😁 He's pretty happy with the nice consistent 7lbs he's got now.

He's gonna pull it in the next couple weeks and take it to a local carb shop for a once-over. His boating season is over, for reasons of lifestyle, so he's getting it ready for winterizing and fixes/repairs for next year. The carb shop is dedicated shop that only works on carburetors. He's got a couple of shop engines he tests and tunes carbs on. He refuses to work on them in their vehicles, though, which is odd, but he definitely knows carbs inside and out. The initial hope was to get it figured out before the end of the season, but I guess we got on it too late. 😐😒

Thanks. Brad.
(937)545-8991