Starting after sitting

[Ron Reaves]

Short of dis-assembly, what special precautions should be taken before attempting to start macs (mostly 91s) that have been sitting for many years? I have several. They, for the most part look good. I know the carbs are dry and will surely need gaskets. Is there a procedure or just use common sense? I don't want to damage them. Ron

[david a luciani]

to be honest replacing the seals isn't hard and it'll give you a chance to make sure all the bearings are free.
old castor oil makes really good stubborn glue if it's old and dried out.
heat and a little wd40 will loosen the castor on the bearing.

at the very least do a vacumn test.
replace the paper gaskets or at least soak in wd 40.
you can sometimes save a diaphram by soaking it in brake fluid overnite.
i have a couple i've been running as found with no problems except dried out gaskets.


dave

[steveohara]

Ron,

If you can't or don't want to disassemble the motors I would recommend that you prepare a mix of 75% gas and 25% regular petroleum motor oil and fill the engine full of fuel. You will need to make a block off gasket for the exuast to seal it up good and let the motor sit full of the mix with the intake manifold pointing up.
Remove the carb and reeds, fill it up and make sure to set the motor in a drip pan to catch anything that leaks out. If the seals are bad the mix will leak out but they will soften and may get better from the exposure to the fuel.
I would remove the flywheel cover, flywheel and points cover before soaking the engines so you can see if the ignition side seal is seeping.
Leave them sit for at least a week to allow the gas to break down any gummed up old oil.
Of course, a full teardown and rebuild is much better but the method described above will do a lot to protect the old motors from the most common problems cause by sitting around for years.
Steve O'Hara

[Ron Reaves]

Thanks Dave/Steve. I think it's time to loosen these old engines up and crank them. At least protect them from further deterioration. Before I put up this post, I removed the stuffer and head from one of them. The engine looked real good outside but seemed to be frozen (couldn't turn it by hand). I was thinking the worse (corrosion, rust, etc). Turns out it was beautiful inside. Very clean, very little wear. Has a full circle crank, it was "frozen" because of a thick coating of that "glue" Dave described. WD-40 loosened everything up but I still have to disolve the old oil residue probably using a method like Steve described. I may take a couple of them all the way down. I just don't have enough gaskets to tear them all down. Thanks again guys...Ron

PS Opening up these things is like opening Christmas presents. You never know what you might find

[david a luciani]

ron ,
new gaskets are available from that guy in canada kartand parts
heres his site
http://www.kartsandparts.ca/store/home.php?cat=2

the bearings and seals are still commonly available seals about 5$ each and bearings about the same.
search this site for seals and you'll find several posts with interchange lists.
i think mcbob has the list posted too.
dave

[John Fields]

Ron,
Sent you a couple of emails and PM's. Please read when you get a chance and let me know. Thank you
John

[Ron Reaves]

Hi John, response sent. Thanks for writing. I'll check this evening. I thought I would group them into matching pairs and sell the remainder...Ron

[John Fields]

Thank you Ron! I appreciate it.
John