CB750f2 Oil leak

[gager5000]

Hello, the title says it all really. There are 2 fairly even sized spots of oil on the floor on either side of the bike after running. It looks to be coming from the top of the crankcase as its covered in oil but there is also a drop on the end of a pipe which appears to lead to the carb but I've not had chance to investigate properly yet. Checking the dip stick over the past week its gone from half way between the marks to dead on the low mark.

Any help would be very greatfuly recieved, might try and add some photos in the morning to try and show more clearly what's going on as I'm not sure if I've explained it clearly at all.

Thanks in advance, Ben.

[finpos]

My money on it being the cam cover seal - they shrink when they get old, the oil runs down the entire height of the engine and comes out in the most odd places. Usually made worse by using the side stand as the oil pools up against it on one side. Try using the centre stand, see if it get suspiciously better!

f.

[gager5000]

*gulp* that sounds expensive and complicated.

Just had it running for 10 minutes and not a drop (did discover tiny hole in exhaust though ) . Its times like this that you realise how useful Haynes really are as finding one for this bike seems an impossible task.

[chris-red]

Oil leaks are easy to trace and the cam cover seal is not a big job at all providing access to it is ok.

What you need is brake cleaner, or any high pressurized solvent spray on liberally till the area is clean, then wait for it to dry (shouldn't take long)

Then cover the area you think is leaking with Talc, and run the engine. You should see it soon enough.

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[fiery tupp]

The hole in exhaust will probably just be the drain hole , common on many bikes
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[gager5000]

nailed it (I think). After trying the talc technique it appears to be a copper seal on the oil pump. Bit of a fiddle 2moro and all will be well, thanks for the help

[gager5000]

Ok, yet another quick question. Need to take the carb off to get access to this washer but cant work out how to remove the throttle or choke cables. Any ideas? am sure its something simple but the downloaded manual I'm using just says to disconnect them and gives no indication how.

[Teflon-Mike]

Are you talking the old, 'long-stroke' DOHC variant of the original 750 'Four' circa 1982ish, or are you talking the short-stroke, CBX derived bike with hydrailic tappets and piggy-back alternator of the early 90's badged the 'Seven-Fifty', else known as the 'Retro' or listed as the F2N? Becouse they are very different bikes, and no, there's no Haynes for the 'Retro', closest is the US Clymar for the CB750 'Nighthawk', which is basically the same bike, but with a few detail differences, like wheels and a single disc up-front, different petrol tank and tail unit... but much the same under the skin.
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[Robby]

The cam cover seal will be easy to change, just don't overtighten the bolts holding it on.

To release the cables you slacken off the adjuster bolts at the carb end and slide the nipples out of their holes. Easiest to slacken off the cables first, then rotate the throttle quadrant on the carb to slacken the cable off it.

Can you definately not reach the washer without removing the carbs? Getting carbs on and off is a horrible job, skinned knuckles are preferable.

[chris-red]