GT40 and perfect pass issue

[360pipelines]

I just did a top end rebuild on my 95 ski nautique and the engine will idle at anywhere from 1500 rpm ro 2500 rpm, and the only way I can idle it down is by manipulating with the perfect pass. I've adjusted the timing some, but it doesn't make a significant difference. Any suggestions?

[DanielC]

The engine should run and idle at the correct speed without the Perfect Pass. Get it doing that first.

[SquamInboards]

What year GT40? I know on earlier build models (ie, tubular manifold) the ECMs from FORD/PCM were faulty and people had issues with high idle and surging. I would just disconnect the PP and linkage and let it run with nothing on the throttle to see how it is. If it is still acting up than it probably was not the perfect pass. When you set your base timing did you remove the spout connector first and set timing to 5degrees BTDC @ 2000 RPM? We set our timing this summer on a rebuilt gt-40 incorrectly at first because we forgot to the spout connector and that solved everything when we fixed it. If you dial the timing in without PP hooked up you can then try connecting it and resolving or isolating the issue.

[east tx skier]

Is it idling high when you first start it up or is it only doing it after you rev up past, say, 1,500 rpm? If it's only doing it after you apply, then come off, power, your throttle cable might be binding up at the linkage where it connects to the cable for perfect pass. If you shut down and restart, the Perfect Pass servo will wind up and, usually, unbind the cable. Check to see if your cable near the linkage for perfect pass is relatively level. If it's not, then that could be your problem.

[360pipelines]

It is an early gt40 with the tubular manifold. I did set the timing at idle, and I believe that i set it at 20 btdc, the label on the cover by the manifold says 30 btdc, but it idled even higher there, so I decided on 20. I also have a resistance spring for the throttle linkage that I absolutly cannot remember or find where it goes. By the way, what is the spout connector?

It idles high right when it starts, around 1700 rpm. The idle will fluctuate after I've been in gear. If I remember correctly the PP cable may not be level.

I really appreciate all of the advice, its been very helpful.

[teamseal]

Well first if you set your timing with the spout connetor in the timing is not set correctly and it may not idle correctly. also disconect your PP servo cable if it is not adjusted correctly.
Did you check for vacum leaks?

[360pipelines]

I located the spout connector and disconnected it. I tracked down my manual and it said to do the same thing. I'm going to hook up the garden hose to it tomorrow and hopefully alleviate the problem. Thanks again.