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Up-dated crank seal

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G

gwoz

Freshman Member
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Updated crank seal

Hello eveeryone I am a new member to the forum so I have a number of questions that you regulars have probably answered a hundred times . I have a 1098 race motor in a 1960 Huffaker BMC Fjr .I have all the info on the car back to 1960 so there is a wealth of information.The motor that is now in the car was built in 93 and was dynoed at 98 hp.I ran it last year 3 times at track days and it runs superb but leaks oil like a sieve thru the rear oil seal.After 2 or 3 sessions the oil gets on the clutch and I get clutch slip.I have pulled the motor and box and intend to fix all the leaks.This required taking the center bulkhead out and completely stripping the car.I changed the front gearbox seal and now I want to fix the crank seal,Mini Mania has the updated crank seal that runs on the crank flange and I have heard conflicting remarks on whether this is a good idea, or should I just replace the standard type seal.I also have rubber seals TAM1089 on the sump pan which I understand are early morris minor .Are these better than the cork seals ? These rubber seals are hard to find. Since I will have the motor apart I will change bearings ,oil pump ,clutch ,water pump etc.The bore looks fine. Thanks for any input.
Graham W
 
Re: Updated crank seal

Tighten up the bearing clearances to a thou or a thou and a half. Use the cork rubber gaskets they are better. The oil coming out the rear labyrth seal is excess oil from the rear main that floods the rear slinger/labryth seal. Once the slinger area is filled with oil it is no longer a slinger. I run all my engine at .001 clearance. Keeping the bearing tight reduces the oil going to the slinger. The slinger can only handle so much oil. I have full on race engines that dyno to the rear axle 110 HP. I don't have massive puddles under any of my cars. I also run my pistons tight as well. I know someone is going to tell me I don't know what I am doing and this is too tight. I have been running my engines like this in competition for twenty plus years. Works on a big Healey too.
 
Re: Updated crank seal

Thanks Roger for the info.Are there any tricks on breathers to reduce crank case pressure ? Is this a factor ? My motor is vented at the pushrod cover plate and the valve cover.
GrahamW
 
Re: Updated crank seal

I vent the 1275 out the dipstick tube. Can't do that on the others. I do vent the 948 out the rear side cover to the rear and up so the oil vapor runs back into the engine. Basically I take the front cover and move it to the rear and then I invert the pipe kinda up and run hose back to can mounted higher than the engine. Some guys put a vent tube in the oil pan near the rear and plumb it up to a can as well.
There are some kits that put a real rear seal on the back of the engines. I have found that mine leak so little I don't need to do it.
 
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