Louisenslin

HI Guys
New to the Forum, I hope im posting this in the right part of this forum.

There are 2 issues:

1: She seems to diesl all the time, I've got BP6FS plugs in, and haven't tried colder ones, the Plugs are perfect gray brownish couler. No pre ignition, Static 10 BTDC and goes up to 32 / 34 at about 3500rpm. Dont know if the holley dubble pumper is the culprit, changing to Edelbrock 1405 this weekend to see if that helps. What else can it be? Would the changing the carb effect this at all?

2:Then the temp used to run around 90 degrees Celcius which was normal, ocationally driving around it goes up to 98 then back to 90 again.

Recently its been going up to 100 - 110 degrees celcius driving around, so I jacked her up, put a spring in the bottom pipe by the pump, replaced the thermostat refilled with 50% water 50% coolent roughly ( 3 litres of coolent, rest water) No leakes etc. Started her last night on the jacks and goes to about 95 then fans kick it goes to about 89 etc etc, which seems normal. will drive tonight and see if its still stable. If not, what else could it be? the water pump " sounds" fine and doesnt leak, any other things to look at?

I've got an AC Cobra replica with a Ford 351 C mild/hot cams, Holly dubble pumper ( busy putting 1405 edelbrock on, weekend ) the Holley needs to be constantly tuned! Petronix III vacuum/ mechanical advance distributer. NKG BP6FS plugs opened the gaps to +-.048 from .035. Ford C6 box, Car idling at about 800 rpm in nautral/park and about 450 in drive. Edelbrock intake.

Thanks for the help!

rmodel65

is youre coolant restrictor in place in the cleveland block and do you have the correct cleveland specific thermostat?

Louisenslin

Jip
The restrictor is in place.
And the new thermostats looks just like the one that came out of the can, the guys at the V8 shop says its the correct one. I will give feedback after I've driven her tonight, I hape it all works fine

JMD

90 C = 194 F
98 C = 208 F
100 = 212 F
110 = 230 F
95 C = 203 F
89 C= 192 F

I translated the temps to F, Many of us here in the US are "Celsius resistant",,, and intend to stay that way....

I have made a few conversions to improve the number of responses....

Well imo since the fan comes on at 203, and then the engine cools back to 192, everything seems to be ok, at idle anyway. If the car continues to heat to 230 while driving, I would be prone to think that the radiator might be compromised, either in restricted airflow and/or water flow.

I have to remember that it is summer in South Africa, and probably close to the hottest part of summer. The car is a Cobra replica, and I have to imagine that this car is pretty hard to cool adequately, not a lot of frontal area, and the radiator can't be too tall. I imagine that the cooling system was working right at "capacity" even when the radiator was new, add a few deposits that might slightly affect flow and/or heat transfer and a person could go from a car with "marginally adequate cooling" to "marginally inadequate cooling" in pretty short order. (I imagine a change of less than 1% heat transfer efficiency could possibly make the difference)

First thing, I would check the radiator for deposits and flow, and make sure that your electric fan setup is not blocking air flow at highway speed.

As far as the dieseling goes, for starters, I would step down a couple of heat ranges on the pluge to see if this helps...

Welcome to the forum!!!!

Louisenslin

Hi jmd

Thanks for all the usefull info. I realy appreciate it.

So i've changed to BP7FS plugs which is one grade colder. I read somewhere that for every 100HP over stock u have to go 1 grade colder. Apparently mine in about 450HP according to an old dyno test i got from the old owner.

Went for a drive ( night) so daytime result might differ. Got oil temp up to 194 degree.

Idling water temp hovers around the 194 - 200. Driving around similar. Driving slowly goes up to about 210. Normal?

Then unfortunately still diesl. Could diesling be from it idling a bit high? Will new tuned carb help?

Thanks
Louis

TommyK

Yes improper primary throttle blade angle can induce run on. What is your idle rpm now? If it is about 800 rpm or lower you may wish to open up the secondary throttle blades to allow more air at idle. This will enable you to close the primary blades via the curb idle screw to get back to a reasonable idle speed and reduce the tendency to pull fuel out of the idle/transition circuits when you shut the car off. There is a balance between initial timing, throttle blade angle and idle mixture screw setting that must be achieved to get the desired idle speed and not be involving the transition circuit at idle.

Louisenslin

Hi Guys

So I think I found my problem, and I hope that I didn't break anything in the process.

Firstly, the edelbrock on, what a lovely carb, smooth acceleration, no bogs, will need to tune a bit more for "low-end" power, but all good. The guys who helped my install it mentioned that the diesling could be due to the high compression Im running 11.5:1 so maybe I must just accept that and get into the habbit of swithcing the motor off in drive instead of park.

Secondly, we discovered last night that the timing keeps on changing!! When I first checked it, it was sitting on 3BTDC! That would have definately made the car run hot!!

So we'll set it to 11 static drive around and check it again and its on 7 or 8, so we took the dizzy claw off, grinded it a little and made it a bit rough, and refitted it, restting timing to 11 Static drove around ( night-cooler) and the temp seemed to be fine, Highway between 194 and 200. And city around 196. So now on Saturday I;ll take it out during the day ( hotter) to see what happens. I've also put a Timing advance limiter in so my all in now is 31, ( mech 20 )

Now before this discovery, I've been driving around for about 62 Miles not knowing that the Dizzy was doing its own thing and struggling with trying to find the overheating issue, the hottest the car got was this past Saturday driving back from the Carb guy before finding the dizzy problem and the hottest the car got was 275, I pulled over for it to cool down and after that it was sitting at 230 all the way home.

The question is, do any of you guys think I could have broken something in this while?
There's no water leakes, the engine sounds fine, not smoking, power is fine, It did however use a bit of oil that I only noticed last night when I checked the oil. a bit less than a pint. Could this have been due to it running so hot on saturday? Or do you guys think I poped something? I guess I just need to drive it aroun=d a bit more and monitor it?

Thanks again for all your advice
Louis