Topic: Drain Plug- seriously stuck & stripped- cb350 (now stuck!)

[mikedialect]

I started on my 71 cb350 JUNKER. This bike is some serious disrepair.

The most pressing issue so far is that I can not for the LIFE of me get the drain plug out. It is FUSED! It's stripped and won't budge. Now, I've had decent results with easy outs, but I've never run into something as stuck as this. I don't think it was ever removed. Any tips?

[relative q]

Craftsman makes some bolt extractor things that bite onto stripped bolts.  I'd probably try buying a set of those and hitting it with an impact wrench.

[dustyc]

I would try warming up the case with a torch, Vise grips and a cheater pipe. 

[Raul CB750K1]

First of all: if you are going to buy a set of extractors, buy the best ones you can afford. I tried to remove a broken exhaust stud in my Sanglas 400Y and the extractor broke! so I had to remove a broken stud with a piece of hard extractor inside!!!

That same bike had the same trouble with the oil plug, but the engine was in the bike. Believe it or not, I used a breaker bar trying to loosen it and the bike would rotate around the centerstand!!!! I needed a friend to hold the bike tight to keep it from rotating until I could loose the bolt that cracked way loose, but fortunately, the threads were perfect, so I just bought a new one and this time I didn't overtightened.

In my CB350 resto, during the engine rebuild, I just noticed the oil plug threads were a little worn, indicating somebody had stripped them. As there was no better time than then, I just bought a lower crankcase out of eBay with better threads and saved me some future hassle.

[mcpuffett]

Hi you could drop the oil pan of & put it in a vice to work on it? or get another pan ? , cheers mick.

[Helo229]

I would recommend dropping the pan and setting it aside with a pool of PB blaster. Let it sit for a day, lock the bolt into the top of a vise, and turn the whole pan.

[droopy]

I would recommend dropping the pan and setting it aside with a pool of PB blaster. Let it sit for a day, lock the bolt into the top of a vise, and turn the whole pan.

heat the drain plug first then use the pb blaster.

[DarkRider]

depending on how bad it is...why not just replace the pan all together?

[mikedialect]

cb350 twins don't have pans. I could replace the lower crankcase cover, but I'm looking to avoid that. I soaked the stuck bolt in a cup of PB blast tucked up under the bike for a day and nothing with a breaker bar and a cheaper pipe attached from a floor jack. Previous to that I ahd sprayed the bolt generously with PB for a few days. I have not tried to heat it up, but I don't have a torch handy either. The thing about this is that I'm not even sure about the engine. I know it turns over, but there was a TON of oil on the head. I was in the process of getting her running to find out where all that oil had come from. Rings or otherwise.

The bolt extractor looked interesting, but based on my previous attempts I'm not sure that would work either?

[GNXFan]

Here is what I used to get the drain plug out of a 69 CL350. I think I used the largest one in the set. It did work on mine. Mine had the bolt part rounded off and also it had chisel marks on it. After I got the old one out I bought a new plug from my local Honda dealer. Yes they're still available. Sorry for the crappy picture. The Craftsman part number is: 952161.

[mattcb350f]

Try tapping the head (or whats left of it) with a hammer. Not hard, don't want to break anything but repeated taps with a hammer will soften things up before you get to wrenching on it. If there is any looseness to the threads at all, this will help crush the little gasket on the bolt which will help it come undone. Trick is firm repeated taps not great big ones.
 Matt.

[Helo229]

The thing about this is that I'm not even sure about the engine. I know it turns over, but there was a TON of oil on the head. I was in the process of getting her running to find out where all that oil had come from. Rings or otherwise.

Have you tried an impact driver on it? I don't know if the sockets GNXFan posted would work with one, but it would be a hell of a combination.

If you're going to be stripping down the whole engine to check it over and replace seals, I wouldn't get too bent out of shape about snapping the bolt. Worst case scenario you have to drill it out and use a tap on it, which, while a real pain in the behind isn't the end of the world, and if you're taking it all apart anyhow the metal shavings would be easy enough to clean up.

If you don't want to go through all that, you could always take it to a machine shop to get done. I had an old briggs & strat engine which had rusted over a few years back and took it to a local shop who drilled it out a few baked bolts and tapped it for me.

[Raul CB750K1]

Do you know the other thread running about "tales of a moron"? When I bought my CB350 it was very hard to remove the oil plug.... until I realized I was tightening instead of loosening. It is difficult to coordinate your spatial vision while bowing at floor level.

You can also try one of those pipe turners (rapid grip wrench) or slack jaw wrench. Don't waste your time tapping the bolt; there is no crush washer but an o-ring, so if it's very tightened it wont crush anymore. A slack jaw wrench and a good mallet -and making sure you hit the wrench in the right direction- and that bolt will come undone in no time.

[mikedialect]

This was the CRAZIEST bolt I've ever dealt with. It took an an hour + of the brand spankin' new heat gun I bought to get it loose. The pipe wrench didn't help, but it did strip it two socket sizes down. Two weeks later, $55.65 and a whole lot of blood and this thing is finally off. I had a spare plug- thank god!

Funny thing, though. I had the bike on it's side for about an hour and I got it back up after I loosened it and now the damn thing won't kick over! One thing after another?

Pulled the plugs. I tried to kick it over after they were out too. Seems to be the same situation with my 69 cb350 engine. If I pull in the clutch the kick moves, but if I let it out it wont budge. Something is definitely stuck! Alternator won't budge a millimeter.

[Helo229]

That's kinda weird. Maybe while you had it on it's side oil leaked through a piston ring or something and flooded a barrel? Or all the repeated bangings knocked the link out of the cam chain? Pick the bike up and shake it a few times, see if anything rattles

I had a hell of a time with my riding lawn mower being seized beginning of summer - I took out both the spark plugs, put a tablespoon of oil in each hole, let it sit for a while and soak in, and the next day it spun free as a bird. I dunno that this would work, but it's always worth a shot.

[droopy]

try rocking the bike back and forth in 2nd gear to get the engine to turn over. sounds like it slipped in between gears 

[mikedialect]

try rocking the bike back and forth in 2nd gear to get the engine to turn over. sounds like it slipped in between gears 

*nods*

I'll have to put the ratty chain back on and give this a shot before the depression sinks in!

[Raul CB750K1]

The kickstarter only works in neutral. Otherwise, it will turn the wheels too. In order to kickstart the CB350 it has to be in neutral.

[mikedialect]

Oh, I definitely did not forget to put it in neutral.

I put the chain back on popped it into second.... and it's really stuck. Any other ideas? Or I suppose my cheap 'kicks over & needs TLC' bike is going to turn into an expensive garage decoration.

[Bob Wessner]

I wonder if something slid out of position in the tranny? Just thinking out loud here, not much help, right?

[antiq]

All that time on it's side you may have a hydraulic lock. Oil filling a space where it shouldn't be. Try putting it on the center stand in the sun for a couple hours. What leaked in might drain back out. Just a thought.

[droopy]

try it in all gears rocking back an forth, question is the cluch working? as in the cable moving the clutch?

[mikedialect]

I think I eliminated the possibility of hydraulic lock. I would have, at this point, loved that! I'm pretty sure that I broke something while hammering on the socket when I fianlly did get the drain plug out. I don't know, though! This is the point where I end up putting the engine under the table and looking for a new one.

[mikedialect]

try it in all gears rocking back an forth, question is the cluch working? as in the cable moving the clutch?

yeah, the clutch is working. Or at least I assume that it does because when I pull it in the kick releases. I could be wrong?

[mattcb350f]

What about tipping the bike over on the opposite side in which it got stuck and trying to free it up. You might even have to give it a few gentle wacks with the hammer to try and get the gears to vibrate out of position again. I'm guessing like most that something inside shifted when it shouldn't have.
 Matt.