Carb overflow

I had an o ring fail on the holley carb. This create a major overflow of gas into the carb so much that all 4 bbl filled, it quickly drained into the engine. I realize to change the oil and filter. The problem is the oil cooler i'm sure the engine ran long enough to pump contaminated oil into the cooler. Iam wondering if oil remains in the cooler or does it drain back into the pan. The oil cooler is mounted high in the back and connected in series with the remote oil filter via the stock oil filter location.

I was going to break one of the lines free to see if it will drain. I might have to have to break loose the secon line to allow air in.

Anyone else ever done this.

I also thought of just putting in cheap oil and filter and let run for a few minutes , Drain and then put the good stuff in .

Concerns about the gas possibly still in a cylinder or the cylinder walls being washed down with gas.

I was thinking of pulling the plugs and putting a shot of oil in each cylinder and running the starter with the plugs out.

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I had a similar situation with a Holley but it was cause by a fragment of PTFE stopping the needle seating properly, and because I had parked on a downhill slope the contents of the tank drained into the (front mounted) motor. God knows how it got past the electric fuel pump but it did. I learned from this, that when you put PTFE on a fuel line connection avoid putting the tape on the first 2 or 3 threads!

When I tried to start it all I got was a heavy thud and I'm lucky it didn't try to fire else I would have hydraulicked the motor.

All I did was to drain the sump, change the filter and refill with fresh oil - no problem. I think all fuel is contaminated with gasoline to a certain degree - and I think your idea of flushing the system is a good one plus a shot of Motor Honey or STP down each cylinder could not do any harm either and spin it over without the plugs in...


Gulf GT40
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I had a bad seat in a carb fill the engine with gasoline, pan and all. was parked down hill and I drained the gas-oil but didn't do a good enough job, later spun a rod bearing. It does get into the oil, so make sure you get as much as the fuel out and change the oil a couple of times as it might save you motor.

thanks for the responses. my plan is to drain oil pan, change filter and drain oil cooler. Bring the car up to operating temps in the driveway. Redo everything again. Drive the car and put 10-20 miles it and redo everything and put the good stuff in now.
hope this is enough i really don't want to experience what Sandy went through..

This also brings up a good poing how many people are experiencing a rubber failure. I believe the modern gas (with ethanol) is causing the rubber breakdown. Holley hot line claims no way. I've heard too many people experiencing rubber seal failure. (Ha Ha no it didn't result in a child)

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Normally the types of rubber used for gasoline and for ethanol apllications are different, nitrile and Buna N. Either is not compatible with the other liquid. Ethanol will begin affecting the o rings and gaskets made to use with gasoline. Manufacturers have since added compounds to reduce this but IMHO it still does a number on the o rings. Gas will hold about 10% ethanol by volume but needs additional chemicals added to keep a higher percentage in solution.There are additional serious problems that occur with the alcohol present that never affected engines and components in past years before blends were introduced. One of the major troubles is that ethanol absorbs water like crazy,one of the reasons we always kept alcohol fuels tightly capped. This presents corrosion problems in all the components that come in contact with modern gasoline.Also,you're not accomplishing anything by adding methyl or isopropyl "dry gas" as there is already a maximum volume of alcohol in the fuel.
In this case,draining as much of the contaminated oil as possible and replacing it with a new batch and filter and draining that after the engine comes up to temperature,will be fine.If you haven't run it yet,pulling the plugs and turning it over(ground the coil or disc the ign first) will purge the cylinders.They don't need to be lubed;that'll happen when it fires up. A.J.
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Thanks AJ what about fuel stabilizer or octane 108 boost does this add to the problem. I was adding octane boost to eliminate a slight engine ping. Added fuel stabilizer because the car sits nov thru march.

The stabilizer(Stabil brand) will save you a bunch of headaches.I use it in everything (bikes,generators,chain saws,lawn tractor) that will sit for more than a month.For extended 'naps' I put just a tiny quantity of Marvel Mystery Oil in too and ad fresh gas to mix it up.Best method is to fill the tank to avoid condensation. Then,run the engine for a while so the mixture gets through the system. I have seen this combination even clear out carbs that had been sitting or dried out /varnished up without being treated.I used to drain everything but the 'top off' method keeps it from drying out and gaskets from shrinking and cracking.Downside is you run the risk of a leak(stuck float needle,etc.) but if you have shut offs,this will not happen. The octane boost does work but is it to cure a problem under hard load/hot or 'normal' driving? If detonation occurs,think about a colder plug or mixture settings.I don't know what the effective compression ratio is so your octane requirements could justify the booster( which should not effect o rings).The fuel stabilizer should not aggravate the pinging condition.You can use a small amount of booster to offset the effects of oil type additives until the tank is refilled.I would try retarding the timing ever so slightly and see what effect it has.Watch your temp gauge. A.J.
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I just notice you are from cheshire. Do you take your gt40 to any shows i've been to many shows in CT, I live in Glastonbury. There is an up coming show in Berlin i believe in april I will be there along with 3 other era gts, My car is Black with Metalic bllack ghost stripes.

Hi Lloyd. Yes, I'm in Cheshire,very close to you.If you give me the show details I'll meet you there.
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I'll keep you posted once i find out the details. I solved my ping problem by backing down the timing from 34 deg to 31 deg. I don't know if its my imagination but it seems to have more power with the octane boost, so i keep on using it. 12oz to 8 gals of gas.
AJ i just found out the show is 4/26 in Berlin I'll be out of town that weekend. there will be plenty of other shows.