Working an idle issue (below thread) I have the TB off and looking at the fast idle cam (FSM F1-36). 2 questions:

On mine, At 77 degrees, the cam roller centerline lines up with the upper of the 2 marks on the idle bar that the wax rod plunger pushes on. Is it suppose to between the two marks? Book figure shows between the two marks but Haynes manual (pg 133, fig 12.5) shows cam roller centerline of lower mark. So should cam roller be between marks, centerline of upper mark, or centerline of lower mark?????

When i pour boiling water thru the wax rod extends but it does not completely separate. It looks identical to the bottom picture in the FSM F1-36. I'm thinking they should not be touching at all the way the book says? Is this right?

https://www.rx7club.com/2nd-generation-specific-1986-1992-17/clutch-switch-high-idle-problem-508121/

 

*******When i pour boiling water thru the wax rod extends but it does not completely separate*******

Frankly speaking, this is where you get to apply your shade tree mechanic skills. If I were you I'd adjust the screw in such a fashion that the cam/roller seperate when YOU want them to seperate or at least adjust so it will seperate. In other words *disregard tech data* in this case.

Either that or buy a new water thermowax if you determine that it's not extending far enough.

 

Thanks HAILERS. I did order a thermo wax plunger Fri. I noticed a couple things doing the boiling water trick:

I did it like 6 times and 2 of the times after it cooled the plunger retracted but the screw/arm didnt retract along with it. There was free space between it (~1/4 inch). I lubed the springs and it seemed to work better.

Also the cam arm had a dip or valley in it where I guess it wore out a groove where the cam roller stops once hot. Is there suppose to be a dip in the arm or is it suppose to be a continuous smooth curvature?

 

I'd guess a smooth contour on the cam.

I've no car to look at where I am. Maybe tomorrow I'll look, if I remember.

I thought I saw a groove/dip in the roller when I looked the other day when I didn't know if the roller was supposed to *roll* or not (outer race should roll).

 

Thanks for all your help HAILERS! I adjusted the wax plunger screw until the roller was at the very tip of the cam (I couldnt adjust it any further) and it did wonders. Took it for a ride and adjusted the TPS and in most part no more 1500 rpm at idle. Sometimes it gets stuck on that little worn 'valley' in the cam but I just pop the pedal and it goes over.

I did hear what sounded like an air leak so I got the stetescope and my green/white check valve is screaming? The one from the thermovalve to cruise. I dont have the cruise cable hooked up. Does this mean anything?

Thanks again........

 

Frankly I didn't know the cruise had a green/white check valve. I don't have one on my S4 n/a car. In the S5 diagram I see a check valve b/t the intake and the water thermo valve ....................I claim ignorance on this one.

The double throttle diaphram should get a check valve somewhere in its vacuum line. Tell you what. Go to your double throttle diaphram and put a piece of vacuum hose on the diaphram and suck. If it does not hold vacuum and pull the double throttle diaphram rod inwards, then the diaphram is busted and you should cap off the line to the double throttle diaphram to prevent air leakage.

 

Diaphram works. I reversed the vacuum hoses and the diapram didnt work so flipped them back and it did work. The CV didnt 'screach' when I reversed them but diaphram didnt work so i flipped it back. The CV is between the thermovalve and then T's one to cruise and and one to manifold. I don't have a CV between the thermvalve and diaphram. I stopped while I was ahead-I'll get to it tomorrow.