427 TI Problems

[William H.]

I have a newly rebuilt 1968 427 435/TI engine that just had valves and tri-power carbs set to factory settings. The distributor and TI was rebuilt by TI Specialties. It is hard to start, one it starts, it runs/idles good with choke closed. As it warms up, it won't idle too long. On the road, it runs strong with no power issues. When you come out of gear at a traffic light, it stalls. I know it's not a lot of information but thanks for any ideas/thoughts.

[William L.]

Re: 427 TI Problems

Bill
Doesn't sound like TI problem to me.. Sounds more like Carb or fuel issue.. Make sure that all of your fuel filters are clean and don't forget about the filter in the fuel tank. When I had had problems with my TI it either worked or didn't work. Since I switched to K&B products, they are in the Driveline, I have had zero problems with my TI.
Bill

[G A.]

Re: 427 TI Problems

Bill
Doesn't sound like TI problem to me.. Sounds more like Carb or fuel issue.. Make sure that all of your fuel filters are clean and don't forget about the filter in the fuel tank. When I had had problems with my TI it either worked or didn't work. Since I switched to K&B products, they are in the Driveline, I have had zero problems with my TI.
Bill

Bill, a little help for the un-initiated please. I searched K&B products in the on-line Driveline and got nothing.
- Dan

[Timothy B.]

Re: 427 TI Problems

Sounds to me like a vacuum leak in the end carburetors, maybe both of them. The throttle shafts or the throttle blades could be leaking air and at idle the car will only run with the choke closed..

[William L.]

Re: 427 TI Problems

Bill, a little help for the un-initiated please. I searched K&B products in the on-line Driveline and got nothing.
- Dan

Dan
They are in the May/June Driveline pages 24 & 52 K&B Special Products ph #770 777 1031
www.kandbcorvetteproducts.com
Great Folks
Bill

[Doug M.]

Re: 427 TI Problems

William, Do you know for sure float levels are correct. Idle speed screws too lean?

Doug

[Michael S.]

Re: 427 TI Problems

How long has the Carb. been seating? Old fuel?

[G A.]

Re: 427 TI Problems

Dan
They are in the May/June Driveline pages 24 & 52 K&B Special Products ph #770 777 1031
www.kandbcorvetteproducts.com
Great Folks
Bill

Thanks Bill!

[Curt S.]

Re: 427 TI Problems

.Dan. Iam just completing a body off of a 69-435. I had a similar erratic idle problem that turned out to be vacuum leaks. I ended up starting at the main tank and working through the systems checking all parts and hoses. With a hand vac pump, I found several small problems and one significant leak along the lower seam of the main tank. My car has power brakes and removal of the tank with the engine in the car is a character building experience. Since repair, the engine performs very well at all rpm levels. Testing and repair of the main vacuum tank whenever the engine is out will be standard procedure for me regardless how the system is working. Hope this helps.

[Mark K.]

Re: 427 TI Problems

I had the exact same problem with my 67 435. Dave Fiedler also rebuilt my TI distributor and tested the rest of my system. It was not the fuel system, it was not the TI system. It was the voltage regulator; you may wish to dial it in at idle.

[William H.]

Re: 427 TI Problems

Mark, thanks for the feedback. How can the voltage regulator cause the poroblem and is it hard to dial it in? Much appreciated. Bill

[William H.]

Re: 427 TI Problems

Fuel is 4 months and I should double check the idle mixture screws. Thanks for the suggestions.

[William H.]

Re: 427 TI Problems

Tim, what do you recommend is the best way to determine a vacuum leak in the end carbs? Thanks for your expertise. Bill

[William H.]

Re: 427 TI Problems

Thanks, Bill. Good suggestions. Much appreciated.

[Dick W.]

Re: 427 TI Problems

William, you can use aerosol carb cleaner to find the leaks. Attach a spout on the nozzle, direct the spray toward a suspected/possible leak. Give it a small blast and if the idle speed comes up, you have found a leak. First thing I would do is to block off the power brake booster. They can be a hugh leak. Then I would start with the intake, carbs, headlamp actuators, headlamp actuator relays. They all can leak and cause your problem.