What next? STILL not running right?

My original wheel is pretty tough too. The hub had pieces broken out in two places, as well as cracks in the spokes/rim. I got the hub built back up with epoxy last winter...and then it sat all summer. It makes a good "cold weather" project.


Guess they just dont make 45 year old wheels like they used to?

Thanks guys..

even after my buddy went out with me that day, and we thought we had it figured out, it was hard to get too excited right then and there. I had been disappointed too many times this summer.


Like I was saying. I still have some carb tuning and prop pitch issues to figure out next spring.

btw, Steve did you get that wheel for your dads boat,hows it look?

Just in time to put it away for the winter!!!

It'll make the muscatine show that much more enjoyable! Cant wait ti FINALLY GO!

A few weeks ago I had a friend go out with me. I was running a 12x10 and had installed a temporary fuel pressure gauge and a downdraft carb. Ran great ...for about 30 seconds. About 5 seconds before it would fall flat on her face, the fuel pressure dropped to zilch. At idle she would run 8 to 9 lbs.

After some dinking around - trying a few different things, we came to the conclusion the electric fuel pump at the gas tank was the culprit. (the only pump I had been running for the past 4 years). The guy that rebuilt my mechanical pump last summer told me it was ok to leave it there. Wrong! Talking with Billy, he said the mechanical pump can actually pull the anti-drainback valve closed...shutting off the fuel supply. (after thinking a bit more about that, wouldnt the mechanical pump pull the valve open?) Anyway, we eliminated that pump completely and it is RUNNING!

The other thing with the electric pump is, sometimes it worked ...sometimes it didnt. Soooo, after screwing away most of the summer, looks like it ended up being something so simple.

I've run it 4 or 5 hrs since. I still need too get the prop and carb dialed in, but it did run. I never thought I'd be so happy to have a 6 banger running!

.

peter1234 wrote: scared you guys off with that one

Peter,
You didn't scare us off. If you read the thread in it's entirety, you would have noticed we already tried to see if the engine was starving for gas!! BTW, it's not!

sorry went back and reread ... try running it without the cover shoot some w d on spray into carb when it feels topped out rpm wise see if the rpms pick up it will at least tell you if its a wot fuel starvation issue (I know it sounds weird but it works on snow machines when you cant tell its leaning out from fuel delivery) plus w d burns when atomized and is safer than any other spray i can think of.

Thanks for offering the input.. at this point anything is appreciated!

Brian,
I cant imagine valve float issues. the head has solid lifters and new valves and springs. One thing that did change a little is the rocker geometry...the head was milled .060 ..

Steve, We ran ours this past weekend with the new solid fuel line. The tach is a little crazy as at times it reads 3800 at WOT and at other times it reads 4500 at WOT, but the engine sounds the same. With a 12x8 it turned in 31.7 MPH.

So your runs 3000 regardless of the prop that it is turning? That is strange.

Hey... I used a buffer at GL...

You sound just like Obama with that comment Timmy.

"That was what I said, just not what I meant."

I may be wrong , but the tool I have seen you use the most is a BUFFER at Green Lake.That requires a lot of trouble shooting ability don't it?????

wonder if two cylinders wires are crossed and not matched to the cam's order?

Jacking with a prop at the moment seems like a waiste of time to me. better head worse performance using the same prop tells me that it's not the prop that is the only issue.

Billy and Tim, I DO appreciate ALL of your input into this PITA problem... Great thing about this site... most everyone has "been there" in some type of situation.

Tim, The prop I changed last year was from one 12x13 to another 12x13(damn river logs), And the second prop did have different characteristics. The engine started "acting up" earlier in the season last year with the 13 I had been running for the whole prior season. Like i said The 12x10 will be on for the next test.

Doc, ever heard of the scientific method?

Steve changed 2 things at one time (prop and engine top end). Result = bad performance. The first thing I would do would be to go back to the old wheel and be sure that the problem is engine related. If that 12x13 prop is an unknown (ie, its performance never characterized), then how do we know it hasnt been repitched to 15" or something crazy? I sure as hell wouldnt be dinking with the cam timing until the easiest and most obvious stuff was checked first.

My apologies for introducing a bit of logic to the discussion. Perhaps if your troubleshooting were better, he wouldnt be here asking the rest of us for advice?

Regardless of troubleshooting, Bruce's datapoint indicates that both the 12x13 and 12x12 props are way too large for a 170ci 100hp motor. Makes perfect sense to me.

Just throwing this out there, since it hasn't been mentioned at all yet:

Is there anything on your boat at all that might cause excessive exhaust back pressure?

I've seen cars with plugged up catalytic converters exhibit symptoms very similar to what your boat seems to be showing. It will start fine, rev with no load fine, but just not accelerate.