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Engine Specific Info and Questions => IDI Engine => Topic started by: regcheeseman on October 12, 2007, 02:07:47 pm

Title: overheating GTD now worse on veg oil
Post by: regcheeseman on October 12, 2007, 02:07:47 pm
My GTD caddy starts to run hot if it sees much traffic and also if I give it some on a long incline.

It has stock boost and fuel setup. And a large FMIC.

The water pump and rad is good although there is oil in the coolant - though I'm suspecting the water cooled turbo is causing this???? dunno why I'm suspecting the turbo!

Anyway I swapped over to a highish mix of SVO veg oil about 60 - 70% veg oil to the 30 - 40% diesel.

The caddy is now misfiring on one cylinder when cold, the situation improves once the engine is warm but is still slightly evident at idle.

Is the veg oil highlighting issues? Any ideas?
Title: overheating GTD now worse on veg oil
Post by: jtanguay on October 12, 2007, 03:10:43 pm
increase the timing a little.  try 1.05mm
Title: overheating GTD now worse on veg oil
Post by: Black Smokin' Diesel on October 12, 2007, 04:37:34 pm
Hot in traffic means your radiator fan isn't kicking in (check the fuse and thermoswitch on the rad). Hot in inclines could be a bad Thermostat, cheap coolant or you could be losing a lot of efficiency in that big intercooler thus less air for the amount of fuel injected (higher EGTs).
Title: overheating GTD now worse on veg oil
Post by: Mark(The Miser)UK on October 12, 2007, 04:48:22 pm
I feel that running that ratio of veggie will cause problems you speak of over a period of time if you are closing down on themixture unless injectors are running perfectly. Try running a tank of straight diesel...

You're not over 82 are you? :wink:
Title: overheating GTD now worse on veg oil
Post by: Baxter on October 13, 2007, 04:52:30 am
Fix the fan!
Title: just a thought
Post by: pariah on October 13, 2007, 12:54:00 pm
i dont know if this works but i know biodiesel is an excellent solvent and they say to change your fuel filter after like 2 tanks because it may loosen up gunk in your fuel system i dont know if a dirty fuel fliter could lean your mixture? but also i agree check your fan sensor/fan in general
Title: overheating GTD now worse on veg oil
Post by: regcheeseman on October 13, 2007, 01:37:58 pm
Thermostat is out, has been for a while, that improved the situation.

The fan works, but with the type of traffic conditions I'm driving in I wouldn't ever expect the fan to cut in at all especially not in our weather.

In summer I have to run with heater on full blast the keep the temp gauge normal-ish.

Normal traffic conditions for me are steady flowing traffic 30/40 mph, but if it slows nearer 20 or I get caught by a couple of red lights or roadworks then the the gauge rockets.
Quote

I feel that running that ratio of veggie will cause problems you speak of over a period of time


tis the second time I've put veg in, last time was 10 months ago

Quote
increase the timing a little. try 1.05mm

Is this for cooler running or for the veg oil? Could I just pull the cold advance and see if the situation improves? would that have the same effect?
Title: overheating GTD now worse on veg oil
Post by: Mark(The Miser)UK on October 13, 2007, 03:01:30 pm
It's the number of overnight stops. I found a deteriation over a few days with starting; but that was running 100% v. and short  [ 2 mile journeys]
A drink of diesel, a bit of revving, and all was right again. :)
Title: overheating GTD now worse on veg oil
Post by: smutts on October 14, 2007, 04:54:25 pm
If there is no thermostat, then the bypass hose will be bypassing the radiator,  i.e. only some of the coolant flow will be getting cooled, get a decent thermostat in there and see what happens. Superglue the wretched thing into the housing, this keeps the swearing to a minimum whilst you try to bolt it back together. Gravity is not your friend. :evil:
Title: overheating GTD now worse on veg oil
Post by: regcheeseman on October 17, 2007, 03:06:56 am
The caddy was rebuilt from a shell over 14months and has been on the road for nearly 12 months now.

The engine was rebuilt during the caddy rebuild.

The rad was flushed and pressure tested

I had three water pumps to choose from, the best was selected and then stripped, checked and fitted.

I have now returned to regular diesel, the poor running + smoke is gone  :D
The overheating is improved but as it was prior to going veggie

I will fit the thermostat I bought months ago, never fitted it because my bikes all run without stats. I appreciate the cold running issue bought hadn't figured on the bypass circuit.

Thanks for the help so far, I'll let you know the outcome.