I’ve found several thru gm stores.

Your fuel injected. Your ecm commands the timing control. OP is carb’d and using the module’s timing, which he believes is not working correctly on his.

Right, my point being that a DUI module could be a good option for ruling in/out his suspicions. Model number of course not necessarily applicable.

Again, appreciate all the help guys.

Found my steering issue. One of the hoses gave up the ghost with another one not too far behind. Weather cracked. I replaced everything.

I've lost a high pressure steering hose before. Managed to get the boat on plane and going straight for ~12 miles using nothing but the throttles. Hitting a few large cruiser wakes along the way made for a white-knuckle ride back to the ramp. It also made a hell of a mess in the bilge. Good to hear you got that sorted.

I'm a bit curious, how you pick the correct carb'ed eng ign module that has the best timing curve to match your custom engs?.

I use Tbolt 4 v-8 20 hp works great.
Sorry to hear about your woes Tom, Hang in there you will get it ironed out.

Well that’s too bad. Was gonna offer you a few more hundred :wink but that prob means you are gonna’ keep it now. :thumbs

:drink:

Some updates.

Snatched the carbs off yesterday and started going through them. All I can is… nasty. They were fresh and good to go when they went on and test-run. Gummy dust in places that shouldn’t have gummy anything. I guess the e10 did it’s thing.

The baseplate to throttle body gaskets were also misaligned restricting the idle feeds some. There aren’t any alignment pins on the baseplates so they shifted a little. When they go back together, I’ll make sure they go back together cleanly.

Lastly, the linkages were setup 1:1. Not that it means anything with what was happening with idle, but it would have been interesting under load. 40% progressive rods are going back on them.

Hoping to get the idle dialed by Friday or Saturday this coming week. Working on the Bullet this weekend.

Some progress.

I rebuilt the carbs and then back to stock. Demon instructions say for a cam under 240@050 and idle under 1000 rpm to close the secondaries and adjust idle screws to 1-3/4 out and to set the idle-eze at 1-1/2 out (my exhaust is 241, close enough). Secondary screws were closed.

Verified timing for the most part - was hard to see in the sunlight but I was close enough to start work.

I was able to get a good idle on the hose, 850 neutral and 12.8-13.0 afr. This was with the secondaries closed and maybe 1-1/2 turns out across the board. The throttle was very snappy and they seamed to be running well.

Dragged her to the ramp and left on the trailer. Verified timing. Port at 34 degrees at 3k. Had to adjust starboard just a touch. Idle afr for both at 10.9-11.2. i didn’t see fuel but I could see float levels were higher than I’d like. I cranked the floats in a half turn and it got somewhat better but still rich. This was in neutral and 850 rpm.

Time to put in gear. Cough cough dead.

It took some time, but I was able to get them to hold 725-750 in gear. Afr floated between 12.8-13.1. I think the neutral idle is a little high right at 1k give or take. Removing the cables from the carbs made the work a lot easier. With them in gear, I could go from idle to load to idle to load with no issues so I’ll call this a success.

The weather changed for the weekend it looks like. It was supposed to be a washout today but it looks like that’s not the case. Hoping to be out later today or tomorrow.

Easier and safer really is determined by the ramp and or dock set up. For me, it would be 10x easier and safer tied in my dock slip.
Also, the angle of the boat on the trailer at a ramp may not be the same as it is at rest in the water. More angle will change the fuel bowl levels.

I’ll need to readjust the floats when I get her tied to the dock tomorrow morning. They were a little more raised on the trailer on land vs on the trailer at the ramp. Still some tweaking to do but getting there.

Impressive perseverance Tom!

Have you checked your rotor phasing?

Should have bought my Cig Tom!!!! Hahaha

I have thought about that more than a few times, believe me.

Have not but considering the rotor only fits or way and timing is the same as the other one and distributor position is identical, I think we’re good.

I replaced batteries yesterday… found one to be a little weak so I’m thinking that may have been a contributor, too.

I would pull the valve covers and run all the valves, and make sure nothing is binding or having some other issue. Maybe leak it down too. A few valves hanging even just a tiny bit will make you chase your tail

Saw the other thread, what solved your issue

Couple of things…

The carburetors were full of ethanol powder. Also, found that one of the meter blocks was missing the mail well plugs (really Barry Grant/Demon/Holley??).

We also found that the batteries were a little weak. That may have caused issues with the ignition even though it was charging at 13.5-13.9 volts at idle. The port/#1 battery was the worse of the two (with the port engine acting the weirdest).

The carburetor issue really was the biggest pain in the ass. They were a real mess.

The carbs were good and clean when they went on and were tested last year. The fuel killed them post winterization in January. Thankful though. I wouldn’t have found the main well plugs missing on the starboard secondaries. That could have been really bad.

What the frig ?

Yep. That was on the one that wanted to run right, too. Go figure.

TomR had four of these on blower motors that he got in a new boat. Ended up replacing them with Holleys because he couldn’t get them running right so I bought a couple he had for sale. I think I found the issue…

TomZ,

What the Hell is "ethanol powder"...?

Thanks. Brad.
(937)545-8991

Here is some extreme examples from several boats this summer i worked on. Alot of other times, it is slighter amts, so looks like slight amt powder vs clumpy as shown below, lots of times just in the fuel bowls but get’s pulled into the metering blocks and etc. Basically, in places the fuel seems to evaporate from and leaves whatever additives don’t evaporate.


https://cimg5.ibsrv.net/gimg/www.off...9d6eccb2c.jpeg
https://cimg7.ibsrv.net/gimg/www.off...7566fbc0b.jpeg
https://cimg2.ibsrv.net/gimg/www.off...1be27130d.jpeg
https://cimg6.ibsrv.net/gimg/www.off...ef8b3246e.jpeg
https://cimg9.ibsrv.net/gimg/www.off...7468df01c.jpeg

SB,

Eewwwe.....

Thanks. Brad.
(937)545-8991

That is just messed up! Is there any additives or cleaners that will help prevent that or break it down so it will pass through and burn?

Eewwwe.... is right.

That's a pretty extreme example but you get the idea. It was yellow and brown and sticky. Handling them, my hands felt sticky like from sugar/honey and was hard to wash off. It was an effort to get them cleaned out.

The smell though... I've smelled plenty of bad fuel before but not with an organic "rotting feet" odor. Nasty. Thankfully, this was not what was in the tank. We drained and filled and replaced filters just to be safe.

Yes, use non-ethanol fuel. Or drain ethanol and fill/run with non-ethanol before putting away. Thankfully, I have Rec 90 right around the corner now so this shouldn't be an issue. I'll also drain the carbs at the end of the season just to be safe.

Do you think if you shut the fuel off and let it run of gas,that it would help this problem when you winterize?

Easy enough to do… I can pull the relays to shut them off.