engine run on

jeff neely · #1 (**permalink**) 11-10-2003, 01:52 PM

Bob I seem to rember something about wiring and engine run on either in this form or in my era book. I can't seem to find this info. I have had a problem with it for some time now and was wondering if you could shed some light on this for me.

Thank You Jeff Neely.

wilf leek · #2 (**permalink**) 11-10-2003, 02:22 PM

Jeff -was this about feedback from the cooling fans causing the engine to run on? From memory I think diodes were the answer to that one.

Or it could be self-excitation from the alternator?

Sorry I can't be more specific, but it may help you with some search terms.

strictlypersonl · #3 (**permalink**) 11-10-2003, 02:23 PM

I remember the same thread. I think that the MSD was getting feedback through the alternator warning light - something that wouldn't happen until roughtly ERA 640. Could be wrong, though.

I don't remember experiencing runon on any cars we've built.

Generally, run on comes from two things: High idle speed and a hot spot in the combustion chamber.

Keep the idle as low as possible. Sometimes when the engine is dynamically timed, it results in too little advance at idle. You should have 8-12 degrees advance at idle. If you have less, it may be necessary to change the distributor advance limits.

ERA Chas · #4 (**permalink**) 11-10-2003, 03:37 PM

Jeff,
Bob's advice on timing is right-on as always and matches my former problem. Adjust initial and idle speed carefully. You may have too much total advance, as I did. Would be difficult to hot start also. If your combo likes a lot of advance you can switch to 100 octane if available, but if you have aluminum heads you should be able to tune for pump fuel under 11:0-1. Inspect your plugs to see what's going on in your chambers. [hot spots, as Bob said]
Good luck,

ERA Chas · #5 (**permalink**) 11-10-2003, 03:43 PM

Jeff,
I forgot to ask but how do you like your Genesis, [current problem excepted] and what is your equipment, who machined it and how does it live? Any info you can share with a "Genesis-hungry" crowd would be appreciated.
Thanks,

xlr8or · #6 (**permalink**) 11-10-2003, 03:54 PM

People have had problems on some cars with feedback from the electric fans. Installing a relay for them and other high amperage devices will cure it if the idle and timing don't do the trick.

Installing relays is a good idea for any accessory that draws large amounts of power so it can get full power from the battery and stay isolated from the rest of the wiring harness.

Mr.Fixit · #7 (**permalink**) 11-10-2003, 04:38 PM

Even with a relay, you can still back feed juice into the ign circuit, a diode can be installed to correct this problem.

CJ428CJ · #8 (**permalink**) 11-10-2003, 05:11 PM

Jeff,

If you're running an MSD6 box, MSD describes a potential fix on their web site. Go to this link and scroll down a ways: http://www.msdignition.com/1troub1.htm.

Chris

jeff neely · #9 (**permalink**) 11-11-2003, 05:37 AM

ERA Chas, my motor is number 27. When we got it it looked very solid and well cast. After we started to go throught the machining process we discoverd some problems. Number one was when they drilled the oil galleys the didn't hot tank it afterwards as to get all the metal shavings out. It didn't even look like they blew it out with air in some spots. What happened was all the shavings rusted together inside the galleys, a real pain in the ass to dig all that stuff out. Number two when they were drilling the oil passages for the heads they never conected. You had the hole from the head deck going down to the oil galley and you had the hole from the oil galley going toward the head but they never met. Minor problems but the block was by no means ready to go togher as advertised. Now that it is in the car and running fine I see a big diffrence in the water temp. It runs about 15 to 20 C colder than my center oiler did. This very well could be that the bore is standerd as my center oiler was 30 over. Hope this answers some questions if you have more I will respond. So far I am happy. We will see when I have a few thousand miles on it though.

Jeff Neely

ERA Chas · #10 (**permalink**) 11-11-2003, 01:12 PM

Jeff,
Thanks for a prompt response. I'm not trying to overwhelm your post, but I do have couple more questions and one more bit of advice.
If you can't solve your running-on problem, Chuck Gutke and his company Cobra Restorers is right in your hometown of Kennesaw. A quality name in the restoration business and also has assembled some ERA's as well as Chuck's personal ERA GT-40. I'm sure they could fix you up.
Your experience with the early Genesis reflects what Keith Craft has posted here. Incomplete machining of galleys the prime problem. Not cleaning blocks sounds like meant to finish machine but a batch went out the door in error. Or they rushed them out to the market. Surely not acceptable.Three year + development, a few more weeks couldn't hurt. If you could share a few more specifics? Compression, cam specs,induction,short block parts, heads and your intended usage? Were you the builder or a pro outfit?
Thanks for your patience and info.

ERA Chas · #11 (**permalink**) 11-18-2003, 04:45 PM

Jeff Neely,
Any luck solving your run-on problem, and any chance for some more Genesis info?
Thanks,

ToyCollector · #12 (**permalink**) 11-18-2003, 08:36 PM

ERA Chas, I know Jeff and his work calls him out of town for days at a time. If he has not responded yet, do not take it personal. His car is awesome BTW. I still love the color he chose.

ERA Chas · #13 (**permalink**) 11-19-2003, 05:29 PM

Toy,
Thanks for the words about Jeff, Don't wish to hound him. Your car is probably "awesome" too, it's a "K" car.