>As soon as your state pollution laws will allow, go to an injector
>system. They need the booster pump also.
Two years ago I installed the TBI system from Howell. It was quite easy to
install and worked first time. I had a few problems getting it to work
right at very low power settings. It seems that the idle air bypass does
not allow enough air to flow, especially during warm-up. The throttle plate
is adjustable but thats not obvious from looking at the throttle body. I
also have Thorley headers so I needed to switch the O2 sensor to a heated
sensor. Thats a must when using headers. But the technical support from
Howell was excellent and the TBI system makes my 455 start and run like
brand new. I was even able to start using regular gas without the engine
knocking. Something I could never do with the carb.
But.... While the TBI system to works very well, I started having major
problems with vapor lock on my Onan!
The TBI system has a fuel return that is used to bleed off excess fuel flow
and return it to the fuel tanks. The return flow is also used to keep the
injectors cool. Unfortunately the fuel return heats up the remaining fuel
in the fuel tanks. That is not a problem with the TBI due to the high
pressure operation of the fuel system. But the Onan does not like being fed
warm fuel.
On hot days (over 90 degrees) the Onan would vapor lock after a couple
hours operation on the road. I tried replacing the fuel pump (thinking it
was bad). Then I moved the fuel pump out of the generator compartment and
on to the frame rail. But it still vapor locked.
The final solution was to add about 10 feet of 1/4" copper tubing between
the fuel pickup in the fuel tank and the fuel pump. This allows the fuel to
cool off enough that it will no longer vapor lock on hot days.
It was not easy to figure this one out. So, if you install an injector
system and start having problems with your generator, consider adding a
cooling loop to the fuel pickup line before assuming that the generator
fuel system has problems.
Dave
73 Sequoia
PS.
I would be curious to find out if anyone else has had similar problems
after installing an injection system or if I am just special...
>system. They need the booster pump also.
Two years ago I installed the TBI system from Howell. It was quite easy to
install and worked first time. I had a few problems getting it to work
right at very low power settings. It seems that the idle air bypass does
not allow enough air to flow, especially during warm-up. The throttle plate
is adjustable but thats not obvious from looking at the throttle body. I
also have Thorley headers so I needed to switch the O2 sensor to a heated
sensor. Thats a must when using headers. But the technical support from
Howell was excellent and the TBI system makes my 455 start and run like
brand new. I was even able to start using regular gas without the engine
knocking. Something I could never do with the carb.
But.... While the TBI system to works very well, I started having major
problems with vapor lock on my Onan!
The TBI system has a fuel return that is used to bleed off excess fuel flow
and return it to the fuel tanks. The return flow is also used to keep the
injectors cool. Unfortunately the fuel return heats up the remaining fuel
in the fuel tanks. That is not a problem with the TBI due to the high
pressure operation of the fuel system. But the Onan does not like being fed
warm fuel.
On hot days (over 90 degrees) the Onan would vapor lock after a couple
hours operation on the road. I tried replacing the fuel pump (thinking it
was bad). Then I moved the fuel pump out of the generator compartment and
on to the frame rail. But it still vapor locked.
The final solution was to add about 10 feet of 1/4" copper tubing between
the fuel pickup in the fuel tank and the fuel pump. This allows the fuel to
cool off enough that it will no longer vapor lock on hot days.
It was not easy to figure this one out. So, if you install an injector
system and start having problems with your generator, consider adding a
cooling loop to the fuel pickup line before assuming that the generator
fuel system has problems.
Dave
73 Sequoia
PS.
I would be curious to find out if anyone else has had similar problems
after installing an injection system or if I am just special...
