Okay spoke to engine builder
He wants me to put a mechanical fuel pressure gauge on engine.
Then take it out
He is going to try to find me an oil temp gauge to put on there as well and see what oil temps are
He does NOT rebuild carbs, he said that he is not good at it so he wont attempt it
He is going to try to find someone that is good at it and make a few calls and see if the carb needs to be done for HP increase or not. I dont know enough about carbs to tell you any of this but I do know that with an increase in HP there should be an increase in fuel delivery and with increased compression and larger bore in cylinder it should require more fuel, but lean or starve the engine of fuel and it should khonk out and studder not poof out the carb right?
Loading up I thought meant too MUCH fuel not fuel starvation
but if that is the case and it is not getting enough fuel
#1 why would it produce a poof at low (1200-1500 ish) rpm's and not up around 3100-3200-3500 area?
#2 how would fuel starvation create more HEAT in the engines oil?
#3 she only does the poof under load NOT at idle
I can rev that thing all day long and have no problem with the poof but an engine doing "work" and being under load will require more fuel than an engine just running in neutral---that I get.
Joe what is wrong with setting carb by vaccume?
I thought that was how it was always done.
Maybe im wrong or thinking of cars too much and not getting the marine setup in my head right.

I am however going to pull the oil out of there (maybe with a drill pump this time and not by hand like a fool) and put in straight 40 weight oil like everyone is suggesting.
That should increase oil pressure due to the actual viscosity of the oil itself but still may cause drop in pressure after hot but maybe not drop as low due to thickness.
If this thing stayed around 40 PSI all day I would not even think twice about it
but since it is at 20 or so that raises my brow for a WTF comment.
He assures me I wont blow it up cause im being careful and cautious and am paying attention to what they are doing and what is going on
That is a good point with the senders RickR, Every other damn thing on this boat needed to be replaced, why not this
Let me guess though, another idioit 700 dollar "marine" part LOL RIGHT?

Jason

swap the senders between the good and bad engine, use a mechanical presure guage as well and insist on a temp guage, I'll try to find one usually means I'm not gonna find one. I don't think folks were suggesting carb needed rebuilding, altho it may if its 10 years old but that it prob needed re-jeting, setting by vacum is fine for idle but the jets need to be correct in the mains and sec 1st. Lean means heat and lots of it,, one of the fastest ways to melt a piston, This is why many are suggesting here you don't find problem by self destructive testing method of just trying this then that and going out and over heating several times till you have a catastrophic failure, hence the coments to GET an oil temp guage.

Jayl

Sorry Buddy but the low oil pressure could be caused by a bad cam lobe causing the oil to overheat. That along with the puffing out the carb and the torture test it went through getting it to run I would suspect a lunched cam. If it were mine I'd pull the intake and check the cam before I ruined some pistons and scored the cylinder walls.

Keep a close eye on the oil perssure gauges. If there is a marked pressure drop a filter may be clogged with metal :mad:

The good news is oil pressure senders are only around $20

From Panchangalpina: "Have you checked the possibility that you may have to much oil in the motor? If you have to much in an engine the pressure can drop at higher RPM because of foaming created by the rotating assembly spinning in the oil. "

I wiped out a differernt new motor (less than 5 hrs) last fall due to this. Pumped down lifters and wiped out bearings. It was in fact because that motor didn't have a windage tray. I was doing the mechanical guage thing under the hatch when I finally destroyed the motor. Don't F*^k around with that too long!! Now both my motors don't have trays and I need to keep a close eye on oil level to prevent temp and pressure problems. It is quite managable though once you figure it out. My motors run like raped apes now!! Hope that is you problem.

You never answered my earlier post on if you still have windage trays?

BT :cool:

Jay

I've done similar mods to my 330's as you have. Cam, compression, head work, ect, and have spent some time getting the carbs dialed in. The first thing you have to do is richen up the secondaries. You have to change the rear metering rods to a much smaller one. The stock one is about .668, I'm down to a .440 and I'm just getting close. I'm going down lower this weekend for even more fuel. All it takes to change them is a #9 torx head screw driver and about 5 minutes per carb. You can order the metering rods at any GM dealer. Let me know if you want part numbers. I have a whole list. Remember, to rich = fouled plug, too lean = melted piston. Which would you prefer ? Let me know if I can help. Good luck, I have enjoyed following your story !

Bo

Rods and hangers...
http://www.carbsunlimited.com/rodshang.asp

Tim T.

So this fool is rebuilding engines w/o a good line carbs???WOW


"He is going to try to find someone that is good at it and make a few calls and see if the carb needs to be done for HP increase or not. "....WOW....should he not have thought of that prior to doing the engine work???

there is WAY more to selecting/setting up a carb than cfm=cid*max rpm/3456*VE

cover your ass and good luck bro

jay, just another helpful hint to save you time.

forgert the drill to remove oil. those things burn up so fast ( the cheap little pumps)

buy (sorry.....) an oil changing can/pump. They have a bycicle type pump on them. pump a vacuum into the can and watch the oil flow in. it works the best with warm oil. so much easier, especially when you have twins...

well I need to get a different oil change method
this is #5 on each engine im going to change them
All by a little hand pump
my arms are bulging and rock hard from this task
Great work out but your back from leaning over hurts like a mo fo.
Back to it
Yes he does NOT build carbs, just engines.
He stated he is NOT good at building carbs so he does not do it for people, cause it will keep coming back again and again.
Okay Cool with the honesty thing but sort of sucks that now there is going to be someone else in the loop.

The set screws I was talking about are on the primaries (front of carb) NOT the Secondaries in the back.
Just thought I would throw that out there
I also did think of something else last night, I have gas that is old in the tank. Granted it has fuel stabilizer in it which will hold it over BUT it is almost a year now (cause that is how long it has taken me to get this tub in the water)
That may have somthing to do with its performance problems as well but I doubt it.
Just because of how it reacts I would think I need to richen up the mixture a touch and add more fuel to it just to prevent detonation but Im going to do what engine builder wants me to do.
Ill let you guys know what is up when I get off of the phone with him today and see what he has to say.
So far I have been patient with him and not ready to choke him to death and he has respected me and not gone out of his way but not shruged me off or blown me off in anyway.
I dont know what is up with the carb thing but I appreciate his honesty in saying that okay I dont do carbs rather than taking them in and possibly making them worse than they were before.
Have to give the guy credit, he has not lied to me or done anything other than bailing on me to go get his harley
Then again maybe im just too nice or too dumb (Joe dont answer that LOL)
Jason

$54 at west marine. do like me. go in together with another boatin buddy. most people only need it twice a year........