Re: volvo penta 3.0L high idle?
I have dealt with this for a long time on my 3.0 GSP-A and here are some ideas:
It is quite possible that it was pushing toward closed before and when installing the manifold the carb was shifted causing it to not push back as far. This could explain why it changed.
The carb base gaskets are really thick, so if you overtorque the carb bolts it can bend the throttle body causing a vacuum leak. It can also cause play in the throttle shafts causing a vacuum leak.
On my original carb and the rebuilt one I bought, the piston assembly inside the choke that opens the choke with engine vacuum (the small hose) was not working and leaking vacuum. I ended up getting a brand new carb from holley on ebay for less than 250 and this had a tighter throttle shaft and working choke vacuum unloader.
If yours has a pcv valve you may want to check that. I really don't understand the use of a pcv valve when there is no way to pull crankcase vacuum with the giant hose going to the flame arrestor.
These things are big carbs (500CFM) for a 3L engine and have to be closed way down for idle. If you have loosened the throttle plates you need to make sure they are rotated to close as tight as possible. You should see just a small amount of the idle circuit exposed when looking from underneath the carb.
I still have mine putting slight pressure with the throttle cable. I push the throttle forward just slightly to releive the tension when storing for long periods. Too mush pressure and it becomes hard to shift
Hope this helps.
Fred
Honey,
Where is the high idle choke, the normal choke is wide open as it should once the engine is warm. I am not familiar with a high idle choke.
Don,
I was able to get it down by setting the throttle cable back and forcing the throttle connection on it. What bothers me is I should not have to do this, I should be able to get the throttle set with the throtle cable not connected.
thanks for your comments
