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Discussion Starter · #1 ·
How often should the oil be changed when running methanol? I put my car on the dyno the other day and when i got back home i filled the cell with pump gas and let her idle for a bit. At first i got quite a bit of water and methanol from the catch can but after a bit it cleared out. Do i need to change the oil every time, if not how can i tell when i do need to?

TIA
Allen
 

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from what i know you will get milky oil with methanol if you dont have enough heat in the oil.but i know some guys change it after every event.depending on how many runs you get in or how far apart the races i would say if you race every weekend you could probably go 3-4 races before changing it.
 

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I've got some guys running methanol & they change the oil every so often. In other words, RARELY.

All you have to do is warm the engine up COMPLETELY at the beginning of each racing day. This will boil off any moisture the engine may have in it. If you have a dry sump tank, remove the cap while doing the warmup so steam & vapors can escape. Otherwise, you can take the fill cap out of a valve cover with a wet sump.

If you have a vacuum pump (either wet or dry sump) you may want to install a removable cap (threaded) in the opposite valve cover to allow the vaccum pump to fully evacuate the system during warmup.

Do you have a way to induce a large vacuum leak at idle? My guys run a piece of 1/2" vinyl tube to a barbed fitting in the carb spacer and the other end is next to the driver's seat with a ball valve on it. This will speed up the warmup cycle considerably.

My guys also don't run any magical mystical oils. Engines always look extremely good during freshing and drained oil looks excellent after weeks & weeks & weeks of racing. No need to change it if the moisture's not in it and it's not full to the gills with fuel. Alky tuning (when done right) doesn't need to result in oil dillution with fuel. If it's injected, use the manufacturer's recommended starting point for pre-set leakage of the barrel valve & keep it as lean as possible.
 

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Discussion Starter · #4 ·
Thanks for the info Rob.

It is an EFI turbo car so i can idle it up and lean it easily.


What kind of oil temps do you normally see. I have a thermostat on the oil line so 180 degrees is common.
 

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For years we always ran Pennzoil Racing oil because years back it was just about the only oil that stated it was for methanol, nitro, supercharged or turbo charged motors. Never had a bearing failure or a problem and it was easy to get. We run a mechanical fuel injection so depending on how many runs we got in we would dump it ever other week.
We are now running Schaeffer Supreme 7000 20w-50 Racing oil and a System One oil filter. We pull the filter and inspect it weekly, fill it it back up, top off the oil and after 20 runs it only changes color slightly.
Like Rob said temperature is the biggest thing. If you never get the motor heated up you will need to dump it more often.
 

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I have been told that rotela is the oil to run,is this true?
 

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I have been told that rotela is the oil to run,is this true?
I do actually know a number of guys running rotela with no problems. Seems the diesel oil has more zinc or some other additives that work with menthanol.
I say the key is to use a reusable filter and check it often. That allows you to make sure there is nothing bad going on inside and you can check out the quality of the oil.
 

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I use Amsoil 60w HD Racing oil and it is resistant to alcohol dillution. So far I have had no problem with it turning milky.
 

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a buddy of mine has only changed his oil once this season.uses brad penn,vacuum pump,block heaters,lean out valve.no issues.oil has never been milky.
 

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a buddy of mine has only changed his oil once this season.uses brad penn,vacuum pump,block heaters,lean out valve.no issues.oil has never been milky.



Moisture is what turns the oil milky.
Burn it off and no milky-colored oil.
 

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Discussion Starter · #11 ·
So the common consensus is if th oil is not milky leave it alone?

Thanks for the input guys.
 

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13B Thats a fast RX3 ya there. A fridend of mine has an RX7 2 rotor and i showed him your vidieo, now he wants to find a RX3. He says he'd go back home to PortoRico and find one, but i think he might find one in the states. Nice job on your car, have fun with it........ TomK
 

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Discussion Starter · #13 ·

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So the common consensus is if th oil is not milky leave it alone?

Thanks for the input guys.
As a general rule that would be the 1st reason to change it. If your running a vacuum pump and heater like some guys you can get more runs between changes. If not like I said drop the filter, check it and if it is milky, looks way thin, dump it. Guys that run EFI should get more runs between change if it is tune correctly. Us that run MFI have to watch closer as running the barrel valve too fat makes the motor nice and responsive but throws a ton of methanol right down in the oil.
 

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what if we use meth on a street car?
do i need to warm the block with a heater each time?
it is not easy to do.

Would it aid if the engine is idled till operating temps? and then driven?
 
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