GMCforum
For enthusiast of the Classic GMC Motorhome built from 1973 to 1978. A web-based mirror of the GMCnet mailing list.

Home » Public Forums » GMCnet » Trip Report (Now my next issue to deal with)
Trip Report [message #171029] Sun, 27 May 2012 21:51 Go to previous message
Jon payne is currently offline  Jon payne   United States
Messages: 495
Registered: May 2008
Karma:
Senior Member
First, thanks to all of those who responded to my post about the Onan. I am going to take a closer look at the field winding terminal ends.

Just came back from a short trip, 120 miles, to a local state park, Turkey Run. This is the first drive over 5 miles since the install of the Rockwell Aluminum Intake so I was anxious to see how it performed after a good heat soak.

We started out this morning, OAT around 85 degs and I noticed I could not reach 60 mph easily. In fact to do so I really had to open the throttle. Normally I can easily cruise 70 MPH. but today it required a lot of throttle to reach 60 and noticed too the engine temp would rise. As I backed off the throttler and reduced speed to 55 MPH the temp would drop to near normal. Normal temp the gauge reads about a third between the 1/4 mark and the 1/2 mark on the gauge. When I would reach 60 or so temps would rise to the 1/2 mark. As I slowed down to 40 or less, like going through a town the temps would return to "normal".

I am thinking that I have a timing issue. When I replaced the intake I removed the distributor and perhaps I did not get the timing right. At the time I was certain I timed it to 8deg TDC but maybe I was on the 4deg mark instead. Could this be the reason for the lack of power? I'm also thinking the mechanical advance could be stuck. Does this sound like a possibility? Note that the distributor is a Dick Patterson that I installed three years ago.

There was another issue I was experiencing. When stopping at a light then accelerating, the engine would hesitate, pop, hesitate, pop several times. I know this could be related to heat but I never experienced it this bad with the cast iron manifold. Could it be related to the first problem?

To summarize, could the lack of power be due to improper timing or a stuck mechanical advance?

Does the hesitation and popping I described sound like a heat issue or could it be related to the timing issue?

What about the high engine temp? I am thinking that if the timing is not correct or the mechanical advanced is stuck, the increase throttle is cause the engine temp to increase.

Thank you all in advance!

Jon


Jon Payne
76 Palm Beach
Westfield,IN
 
Read Message
Read Message
Read Message
Read Message
Read Message
Read Message
Read Message
Previous Topic: [GMCnet] CB Radio
Next Topic: [GMCnet] CD player that fits
Goto Forum:
  


Current Time: Tue Nov 19 05:43:37 CST 2024

Total time taken to generate the page: 0.00683 seconds