Fuel leaking out tbi......?

[yukntukn22s]

Ok Ive been searching on this for a while now and it seems the only to fix my problem is a lathe, which I will do as a last resort but I wanted to run it by you guys for some suggestions. Anyway under intial startup and when I let off the throttle at some point, there is gas pushing out the tbi shaft and down the throttle spring into a small pool of gas under it. I would say in a 10 min. drive from startup to cutoff with no heavy driving it accumalates around a teaspoon of gas. I can get a pic to point out exact location but you should get the idea. The setup I have is a stock tbi housing with a afpr and running 10lbs of boost. The truck runs great and does not run rich, the fuel pressure at idle is 13lbs which is close to stock and the afpr is boost referenced 1 to 1. I need to find someway of stopping the fuel from pushing out. I am open to all suggestions, let me know if you need any more info.

[yukntukn22s]

No one?

[andrewdirt101]

are your injectors leaking?

[Whifflebat]

Pics would be useful. I had a leaky regulator once, it was leaking at the big rubber gasket between the two pieces if i remember correctly.

[ragmc]

I had the same problem fuel was leaking from the butterfly shaft when I had the tbi gone through they also machined and put in new bushings. I still get a little fuel out of there but not as bad.

[yukntukn22s]

Originally Posted by ragmc

I had the same problem fuel was leaking from the butterfly shaft when I had the tbi gone through they also machined and put in new bushings. I still get a little fuel out of there but not as bad.

I use to get a lot more fuel, but I have minimized it to where its at now. What do you do when you get a small pool goin on?

[ragmc]

Nothing I just keep an eye on it and clean it up when I see it. I almost bought a carb box like what they use for a carb motor to put the tbi in.

[cancritter]

butterfly shaft needs new bushings...once worn it will throw off your tps causeing probs

[ragmc]

Its not that much fuel

[BLOWN91350SS]

Here's another guy that had the exact same problem as you with a centrifugal type blower running 10+ lbs of boost. This is the only option/solution:

I then contacted CFM technologies. They said they have gotten lots of inquiries in the past from guys with FI applications and for an extra $100.00 (added to the price of their ported TBI of $229.00) they will machine sealed bearings into the TBI housing which are press fit onto the shaft and epoxied and press fit into the TBI. That sounds like a winner so I just ordered one. I will post up some pictures when I get it next week and let you guys know how it worked out.

Here is a picture of it from their website:


Here is the link to the TBI I purchased. http://marine-performance-parts.com/...rgmtbi74l.aspx

His follow up post:

OK, got my TBI today from CFM. One week on the nose like they promised. Installed it and lo and behold no more leak! I ran it for at least a 1/2 hour. Drove it around under boost and normal driving. I would have normally had a puddle by now, no doubt. There isn't even the slightest hint of a leak or even gas odor. The kicker is I actually noticed a little more performance. It flows 720 CFM instead of the stock 640. I also noticed I have more boost now and the pressure comes up a lot quicker. I must have been losing more pressure than I thought out of the shaft. I should have taken a picture, but what you can see from the underside is the sealed bearing and some epoxy. Nice setup. Definitely highly recommend CFM technologies.

Now I'm finally done. It's all waxing and driving now.

If you are a member here is the link to the full post: http://www.454ss.com/cgi-bin/yabb2/Y...m=1207783422/0