three strikes?

[parrot820]

I've been busily cleaning the engine to get it ready for a repaint in the near future. Well, and to get 3 decades of grime and oil off of there.

I started with the bottom of the engine, took the belly pan...err strainer...off, cleaned that up and put it back on, and have been busily scrubbing for the past few days. I must say, the bottom of the engine looks pretty spiff right now, too bad nobody every sees it. Well, usually...

Anyway, so I decided to try and remove those two sheared off header bolts.
I had my doubts since I haven't had any luck drilling out bolts up to this point, I usually end up being able to vise grip them out. Yes, I know, that's not a good way to do it, but I hadn't read that post until recently.

So I'm drilling and got pretty far in to the one that was sheared off even. Tried one extractor and it didn't phase it. Tried another one that required tapping it in and then twisting. Tap...tap...tap..snap!



I did the one thing I've read over and over to not ever do...break the extractor off into the stuck bolt. K, so onto the other one that's got a bit more to grab onto, but it ain't movin...and its disintegrating as I work on it.



Fine, I'm willing to buy a new cylinder head, especially since the one on there is in such bad shape anyway. I've already got one lined up from Andreas and I just need to work out the delivery details.

So I flip the engine over again to start cleaning up the rest while I figure out what "real" work I need to do next. While I'm cleaning I notice the case where the engine bearing (I think that's what it's called) goes in is fairly torn up. I know it took some doing to get the bearing out of there and it's cover was broken when I bought the bike:



but I knew that going into it and figured I'd just replace the cover and that'd be that.
Well, looking at it again, without all of the oil and grime on it, I notice that part of the actual engine case has been repaired:




Great, so now what?
I this OK, will it last?
Should I not worry about it?

Or does this, plus the sheared header bolts, plus that small hole at the back of the engine, mean I'd be better of finding a whole new engine at this point? Or am I worrying too much about little things?

I'm assuming any "new" engine I buy will have its own potential problems that may or may not be more serious than these, so...dunno. I don't want to give up right at the start, but I also don't want to sink 3x into the bike than what I paid for it.

Thoughts?

Patrick

[jmnjrpa]

First off, does the engine turn over? Does or did it have compression? Looking at the other problems I would say you don't know about the tranny yet. Hole in the engine??If you can get that cover to seal it should be alright,but.... My concern would be the engine was in a wreck and may have other issues you won't find until too late. My 2 cents would be to advise getting another engine and keep that one for parts. I believe all the problems could be fixed but will take time, tooling, and expertise. This may be a good one to overbore and prep out.

[redbone]

it may be time to drop back 5 yards and punt. i usually measure projects like that in cursing, grief, hairpulling and general misery involved with the fix. winter is a good time to pick up a parts bike with a better motor than what you currently have.
JMHO

[XSokieSPECIAL]

I'm with jmnjrpa,

I think you need to set that engine aside for parts.

You can disassemble it later just to see what makes it tick, and to see what you have for spare parts.

Concentrate on the frame and electrical and such. Get the rest of the bike checked out and be sure you have something WORTH buying another engine for.

IMHO

[Rev.Rick]

Ditto to all thats been said. With what you can see, I would wonder about what you can't. Looks like the engines has seen some abuse, so be very careful about throwing good money into it only to find later that the engine was junk. My concern would be what kind of abuse would cause the block around the bearing to break. Because of the side to side thrust that bearing may encounter I would be very sceptical of any repairs made. My experience (which has much room for improvement) is that once a stress area like that is cracked or broken it only gets worse. There may be other cracks and hairline fractures in the block or around the damaged areas that you can't see and will only be revealed one day when your tooling along. I would suggest aleast (maybe others would agree) get yourself a crankcase thats not so beat up and go from there.

[tarzan]

Whoa

Hold the bus!
Before everyone gets worked up, why not run a compression test and see if the motor is really in bad shape.That repaired area looks like it carries no load or stress, so if it seals, I would get a cover and button it up.
The header bolts can be fixed fairly easily also.You just get a carbide burr and dremel a hole down in it.Then dig the extractor out.Then drill the bolt out starting with a small drill bit.Then step up to a lttle bigger bit until you see the ridges of thread.At that point you can take a dental pick or sharp object of your choice and peel the thread(it will come out like a little spring or wire) out of the groove.
On the one that doesn't have anything broke in the bolt, just take an 1/8" drill bit(unless you have a small center drill) and drill in the center of the bolt.Now you have a small hole going down through the bolt.BTW-you know you are through the bolt when you break through the other side and it gets real easy to push.Now, again step up in size of drill to a little bigger bit,but not the same sixe as the screw.Step up till you just graze threads.Dig out thread.

You're problems aren't big yet.So, if I were you, I would find out if the motor is good before going out and buying a whole engine.Unless you have money to burn.lol
JMHO.
Rick

[Incubus]

I agree with Tarzan, with one minor exception. Go to Harbor Freight. Get a cheap set of left handed drill bits. They bite counterclockwise. Often they will grab the broken bolt and turn it out before you ever get near the threads.

I've successfully reused cases in much worse shape than those.

Patrick

[Ivan]

The head can be saved pretty easily if you take it to a machine shop and tell them there is a broken off extractor. Solid Carbide will work through an extractor pretty easily. If the guy is good, he can mill out the broken piece to the point that there is only the thread left, then the thread just spirals out. Metric bolts usually require a regrind that is close to the minor diameter of the bolt.
As for the case, if you take it apart, and have it welded up with a heliarc, it would be fairly easy for a machinist to rebore that hole.

But for the general home mechanic, a new case would be the way to go. I would keep the head though, that should be relatively cheap.

And for future reference, Aluminum expands more with heat than steel, so before extracting next time, heat the area up really hot with a torch, it should help them come out much easier.

[jmnjrpa]

Hey Rick,

That's the first thing I asked him.

[parrot820]

Thanks much for the replies everyone.

When I started this, I figured there'd be a go/no-go point on the whole project if it went beyond my skill level, with my skill level being close to nil.
I've hardly done any mechanical work, so I knew this would be a learn as I go type project, but that I'd have to bail if it got too technical. Or, if not bail on whatever was broken and buy a replacement. Of course, I was hoping I wouldn't need a whole engine.

So, what I'll do is take the two different approaches suggested here and see which works best.
I'll drill out the header bolts and hopefully save the threads (otherwise I get into further unknown territory), jb weld the hole, and hope the patch on the bearing housing holds. Worst case, I get to learn about drilling out bolts on a part I already know won't get used, best case...it works.
...and...I'll track down a new engine. I'm willing to pay ~$200 for a good running engine and based on "buy it now" prices on ebay, that's probably doable.

That way I can tinker around with the existing one and if I get far enough along, I'll give it a try. If not, I can use it for parts if needed and just use the new one.

What I don't want to do is give up on the bike. I'm way too curious about actually riding it now to not put it back together. :-)
I'd planned on just selling it after I was done, but if this keeps up I may just need to keep it forever after having put so much effort into it.

There have been several questions about compression testing. I didn't. In my rush to get the project going, I dismantled the bike without doing that basic check, or really any other check. Noob mistake #1, I guess. At this point, with the engine out of frame and everything in pieces, is it even possible for me to do a compression test?

[Larrym]

Minor Heroics

Patrick,

I second the use of left handed drill bits for the remaining broken bolt. I also second the use of a torch: heat it up, let it cool, heat it up again, let it cool, repeat 4 times. This expansion and contraction wreaks havoc on any rust/corrosion keeping the bolt from turning.

As far as the engine case is concerned, it's clear that there's been some form of trauma. Whether or not the damage/cracks extend into anything critical is yet to be known. It's a 50/50 chance so far.

I'd proceed with "guarded optimism" and work on all the small stuff needed to do an actual "Start/Run" of the motor. If it does run then you can investigate those cracks further for oil leaks and such. Let what you find determine whether or not to dump any more $$$ or time into it.

But in the end you'll know if the motor is unrecoverable. If it is then most times you can get a second donor bike with a lot more usable parts .

[jmnjrpa]

About drilling out bolts.

Works good if the person doing the drilling can keep the drill perpendicular to the plane and in the center of the bolt. Not very many people can with a drill press or hand drill. I have been machining over 40 years and have screwed a couple up with this method. This being so, I believe a combination of these ideas will work best for him. Drill well under the minor diameter of the bolt and heat the head (in an oven) then extract while still hot. Do not apply local heat as this tends to warp the head. This method was most likely what Ivan was detailing but I wanted to insure you knew about the head warpage issue.

[jmnjrpa]

Obtw,

Grind a flat area on top of the bolt and it will be far easier to get the drill started in the center.

[jmnjrpa]

I should have read Larry's post

Larry is right about multiple heatings. But I still suggest using an oven.

[DGXSER]

If you go the route of gettign a replacement engine, find someone you know and trust to get it from. I have seen some engines that were "Good engines" that wound up needing new gears, had a bent valve, an oil pump not functioning due to gears off of shafts. Alot of time and effort and money went into making that engine actually Good. So try to find a trusted source rather than the ebay route if possible.