1970 T500 Crankcase Drain Plugs: which bolts are they?

ericsattic

Hello, I am a newbie to this forum and just got a 1970 Suzuki T500-III. I last rode one back in the late 70's and have quite a bit to learn. My problem is the carbs flooded out (petcock left on "prime" overnight). I drained the carb float bowls but I want to check to see if gasoline is in the crankcase before I try to start the bike again. Can someone post a photo of the bottom of the T500 crankcase, together with a pointer showing me which bolts are the crankcase drain plugs? I would hate to loosen other bolts and possibly break a seal, mistakenly open the gearbox drainplugs, etc... In that regard it would be helpful if the gearbox drain plug(s) were pointed out in the same photo, if possible, to avoid confusion. I have an old shop manual but the images are faded and the one I found which attempts to show the crankcase bolts is particularly bad. Thanks, Eric

dorT500 · Posted: Tue Aug 31, 2010 3:13 pm Post subject:

Also see link below...

http://www.3cyl.com/bulletins/t3-1.jpg

Click on pic to enlarge.

ADD Edit; Oops, got turned around here a little. While I have used the two bolts circled in the bottom pic to completely drain the transmission.....by the book you may want to use these two in the upper photo.
Edit; Bottom pic deleted. correct pic showing

ericsattic · Posted: Tue Aug 31, 2010 7:11 pm Post subject:

THANKS for this informative post and photos! After reading it I went to the garage, took out the plugs, and sure enough, my crankcase had gas in it. I drained it out, left the drain plugs out, and also pulled the spark plugs out. Then I slowly turned the motor over to be certain it all came out and I will let it sit overnight with the drains and spark plugs out with hope that any lingering fuel will evaporate overnight. Should fire up tomorrow as it was running strong before I flooded the carbs. With regard to the gearbox drains, thanks again. Don't know why there are three but a guess is that there are certain cavities to drain in the gearbox and/or one is a main drain and the other(s) serves as a vent to make sure all oil drains out. I will use the two indicated in the upper photo but may research this further to see why there are three. Heck, I probably will take all three out when I drain the gearbox...

Finally, I saw that Suzuki service bulletin some time ago while doing some cursory research before my purchase. After reading it I was hesitant to buy a pre-'74 T500. But many people I have spoken with said the unmodified 1200cc gearboxes are generally safe if they are not ridden too hard. My '70 only has less than 8300 original miles and the gearbox has not been opened up. But in the future if I do that I would certainly like to do the modification to increase the oil capacity to 1400cc. To bad my research indicates the part listed in the bulletin is no longer available. People claim they can fabricate it but I am going to keep my eyes open for one. Again, thanks for the photos and info. Regards, Eric

dorT500 · Posted: Tue Aug 31, 2010 8:25 pm Post subject:

Bikegeezer

CaptCatFish · Posted: Thu Sep 02, 2010 2:34 am Post subject:

What does the detent plunger do? Will my transmission eventually self-destruct if I accidentally removed it but replaced it after draining? I've ridden the bike since and everything shifts just fine.

I guess I'm looking for something else to worry about. (You'd think I have enough to worry about since I've got to do a complete tear-down of my T500 and have the crankshaft rebuilt with new inner seals).

CaptCatFish

Freaky_1 · Posted: Thu Sep 02, 2010 5:00 am Post subject:

lol you should be fine...............................

I say this as I did just the same and I guess I must have moved the shifter or something because it wouldn't go back in till I lined everything back up.

If you removed it, replaced it and have no issues, I'd think you're good to go there.

dorT500 · Posted: Thu Sep 02, 2010 5:48 am Post subject:

A detent bolt (spring loaded) is used to hold the shifting drum when the drum is in it's various gear positions. This particular one is also magnetized. As I mentioned before, I have removed this bolt dozens of times and though I made a point of never shifting the tranny while the bolt was out. Actually, just picturing the set up in my mind right now (been a long time since I last had the motor apart) I can't see how it would make big problem even if you shifted the tranny. The bolt follows the drum shifter..not the other way around. I may be forgetting about something here but that is just how I am seeing in my mind right now. The bolt/spring loaded cap rides around the drum shifter and into dimples around the drum shifter as the tranny is in the various gears. I should just tell people to use the other two bolts to avoid any confusion/concern/mishap. Picture is just showing one of the few dimples.

BenEberle · Posted: Fri Sep 03, 2010 12:04 pm Post subject:

Oooooo....a 'clutch drain'?

When changing the tranny oil, should that be drained as well? I didn't do that on the initial fluid purge. Just pulled the tranny drain and refilled with 1400ccs.

Bikegeezer · Posted: Fri Sep 03, 2010 8:41 pm Post subject:

CaptCatFish · Posted: Fri Sep 03, 2010 11:21 pm Post subject:

I've painted the bolt I-will-never-remove-again-as-long-as-I-live-so-help-me-God a bright orange just in case my Old-Timers disease has gotten worse before my next oil change and assuming I can remember why I painted it orange Very Happy

.

CaptCatFish

ericsattic · Posted: Wed Oct 13, 2010 7:21 pm Post subject:

Bikegeezer / Stu - I just gotta say: your labeled photo referring to the detent plunger, etc... is freakin' awesome! I officially mandate that you be given the Hugh D. Mann award for rice burner excellence. Man, I wish you and dorT500 were my next door neighbors! Best Regards, Eric, Fairfax County, VA.

Russell · Posted: Wed Oct 13, 2010 7:30 pm Post subject:

Have to endorse your affirmation.Stu has such a clear and easy to understand way of explaining things that are incredibly difficult for many of us lesser mortals to find our way through.Even if I no longer had bikes I 'd follow this forum to learn,and enjoy the coaching from such constructive and knowledgeable mentors.

dorT500 · Posted: Thu Oct 14, 2010 5:10 am Post subject:

ericsattic · Posted: Thu Oct 14, 2010 8:23 pm Post subject: