This is the sixth part (check out part five here) in our extremely popular video series in which Todd Muller, Head Motorcycle Tech here at Lowbrow Customs, disassembles a unit 650 c.c. Triumph motorcycle engine and rebuilds it. Todd takes us step-by-step through some sub disassemblies including, removing the crankshaft bearings, rods, and the dreaded sludge trap tube. Todd also disassembles rocker boxes along with valve removal, showing you what to look for and how to know when certain parts need replaced. You can check out the Triumph 650 Motorcycle Engine Disassembly & Rebuild - Part 7 to continue following along!
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You can read a full transcription of this video below:
Okay, we got some subassemblies to deal with on our motor teardown, we're going to work on the crankshaft now.
We've got a couple things we got to do here like this pesky bearing that's very tight on there. We have a couple of pullers here we're going to use for that. We have this polar right here. I’ll show you how this works. Pretty simple, not very expensive. I believe, there's a special factory tool. It looks very similar to this. I'm just going to open that up, get it underneath the bearing, I'm going to tighten these down and that's probably good enough for what we're doing. Then, we have one of these types of polars. We're going to start a bolt in one side of it and then we're going to pin a penny on the end of the crank because you want to always protect your crank.
You don't want to go shoving the tool down in the -- where there's some threads. We got to open this, I’ll turn this out. Then, you can get your other bolt in there. Pretty simple stuff, nothing complicated. Make sure both your bolts are threaded in the same amount so this is pulling evenly. Get our penny centered. You have your three quarter inch wrench and look at her, she's coming right off of there. Piece of cake. Here she comes. No problem. No harm, no foul. Next thing we're going to do is we're going to take the rods off. We'll go ahead and flip it over. The reason I'm doing that is because the sludge trap plug is on the other side. You also may notice I have some aluminum soft jaws in my vise.
That's because my vise has a knurling on it for gripping things and we don't really want to be gripping the crankshaft or the bearing rides now, do we? Next thing we're going to do, we're going to go ahead and grab a quarter inch Whitworth socket and take these off. Fasteners here on the rod caps. No big deal. Now, what I always like to do on my rods -- some people put punch marks on them to denote which cap goes to which rod, it's imperative that the caps stay with the rod they came off of. The other thing I like to do because I want to make sure that when I put this motor back together that this particular rod ends up in the same place on the crank and facing the same direction.
What I’ll normally do is I’ll just clean off that portion of it and since my sludge trap is facing up, I'm going to write ST and then I'm going to write out. That denotes to me that this rod came from this journal on this crank with this side facing out. Once you get the bolts off of there -- I mean, sorry, the nuts. Just going to wiggle it, wiggle it, jiggle it a little bit and there you go. Now, I’ll show you the plain bearings here that are going to get replaced. Right here's your plain bearing that rides on your crank. That's what does the wear item. That just slides out of there like that. See that? They're generally marked if they're oversize, I'm sorry, undersized because basically when you take these off of here and then there's also another one here.
For you guys that work on small-block Chevy's plant, it's called a plain bearing. Plain bearing. I'm going to put my cap back on there. I see there is no markings on this, so that means it may not have been a part before. I'm going to put my nuts back on here too. We'll go ahead and take the other one off and then we'll take a look at the journals on the crank and see what condition those are in. I'm going to pay attention when I take this one off and I'm going to mark this side of the rod out because it's going to face out when it goes back together.
Once again, pull that carefully to take that off of there. Okay, came off like this, so I'm going to flip it over and I'm going to write out on this rod as well.
Pretty simple. No big deal. After you get your rods off, as you want to take a look at your journals. Those look pretty clean and nice. Now in a high-mileage motor, what happens is this bearing surface that rides on there spinning round and round, round and round and round she goes down the road you go 80 miles an hour all day long, it's going to wear that surface out. If it wears it down and you take these off and you see a kind of a copper color on there, it was definitely time for a rebuild. The other thing you can check before you take your rods off is you can pull on your rod this way and see if there's any play and there shouldn't be because this is a precision fit here.
You're going to find some play on the rods this way. That's normal. Don't worry about it. Nothing to worry about. You can look on the bearing shell on the backside of it and I could plainly see that this one is marked STD which denotes standard. Now, let's just say everything was looking pretty bad here and you needed to send this out and have it redone. You can do -- they're going to remove some material from this at the machine shop. Then, you can get a different bearing like this and it's going to be ten thousandths under sizes what they call it. Basically, it'll be a little thicker than this and then it will still work right. If your crank looks terrible, you can still use it by having it machined.
This one looks very good. Nice and clean, no grooves, no wear, no marks, the bearing shells still look in good condition so it'll go back together with a standard -- a new set of these and that'll be that. Let's just say you did have some wear and you wanted to measure this. You can get away with doing it with a vernier, you don't have to have a micrometer. You're just going to -- this is going to be in inches. I have the book there to tell me what a standard crank should measure your journal and I'm getting 1.624 inch. If I go over here to my book I can see that a standard for the bearing suitable crankshaft size for standard bearing right there 1.6240.
I can go ahead and check the other one just because we can. Not a problem. I'm seeing the same measurement, 1.624. Cheap way to check it. I'm not concerned about these. Totally reusable. Now, we have our fabled sludge trap. My God, there's a sludge trap in here and should you be concerned about that? Probably, because a lot of times when you take these out this thing's packed full. Basically what that sludge trap is, it's a centrifugal filter. As the crank is spinning around, it's throwing stuff against the side of it, impurities and crud and then it sticks and it builds up from side to side. It's not going to build up from top to bottom. Here's a new sludge trap right here. This is what it looks like. Down inside here, that's your sludge trap. Basically, you'll notice there's some holes on here. That's pressurized oil, so that these bearings get pressurized oil to lubricate the rod as it spins around. Now, if your sludge trap gets completely packed full, what do you think is going to happen? Your rods not going to get any oil. Next thing that's going to happen, the rod may come out the side of the crankcase. Then you'll end up with something that looks like this. I'd say that rod went through the crankcase. Probably not a good thing to happen to your motor. Renders it pretty much useless.
Easiest way to get this out of here that I’ve found is when I used to work for Harley Davidson, I bought this tool right here. I got it from Napa. There is a part number on here. It is a one sixteenth drag link socket for a car. Imagine that. What I did when I was working at Harley, I actually ground the edges of this down and what I was using it for was the caps on Evo, Shovelhead, Panhead, oil pumps. There's also one on the crankcase where the witches hat is but that's a story for another day, but any rate draggling socket from Napa. In case anyone's wondering, the part number is NB95. It will be straight across when you get it, so you're just going to take it to your grinder and you're going to make it rounded.
The reason for that is because the plug is rounded. Here's a sludge trap plug right here, see it's got a slot there and it's rounded. That'll fit in there real nice. Look at that. Gives it a nice bite. It'll also be some punch marks on here from the factory and that's so that this doesn't loosen up. A lot of people say you have to drill those out, I’ve done it both ways. We'll go ahead and we'll show you -- I did this previously at the shop because I still don't have a new compressor for the garage and I do use an impact gun on this job.
I like my half-inch Ingersoll. Haven't met anything that it can't break yet. I think, I may have mentioned that in another video or previous videos. This gun here, if it doesn't loosen something, it will break it off. It's not likely you're going to break this off but at any rate. We'll cut to the other portion out to shop, we're going to put this and we're going to go [drilling sound] until she comes out of there.
We got our plug out, let's have a look. Holy moly, did you look at that? She's so darn clean, there's no need to even take it out of there. Geez, I know you guys want to see me remove a sludge trap, don't you? All right. We got another crank over here that will do it to it. I can't really see any reason to take this one out. It just needs a good cleaning with some solvent or some brake clean, some compressed air. Bada bing bada bang. We're going to go ahead and remove the sludge trap out of this here other crank I have hanging around the garage that also needs a rebuild.
First thing we got to do is, we have to took the cap out, the sludge trap plug. You have to take this bolt out because there's a nubby on it, you'll see in a sec here when I take it out that indicates on that hole right there. Once again, Whitworth. She's a tight one, goodness. My god, she's tight. Here she comes. A little bit of lube doober on there never hurt anybody. Boy, here she comes. There she is. There's some kind of weird compound. Boy, she was Loctite it or something. Or maybe they didn't have Loctite back down, they put something on there. But any rate, there she is. See that? Bada bing. That's in the sludge trap.
Now, you may have looked at our -- previously looked at our tech tip on the website and I used to do this a little differently. I used to use a very large MPT tap. I'd put it in there and I'd crank it in and then I'd hammer it out, we're going to do it a little bit different today. We got a tap here and what we're going to do is we're going to lightly tap some threads in there. This is a 5811. Then, I have a corresponding bolt. You may also notice this is a tapered style tap. See how it kind of comes to a taper there? You don't want to use a bottoming tap, you want to use this style tap. We're going to drop that down in there and maybe we'll just give her a little tap. It's kind of get it straight there and then we're going to put some threads in her. We're not really trying to cut threads, just want to get something for that bolt to grab onto.
The other thing we want to try to accomplish here is we want to try to get that sludge trap to turn in the hole. If you can feel that thing turning, that's good. That means, it's going to come out. We don't want to put too many threads in there because we don't want to push it out. Maybe one more turn and let's take her out and see how we're doing here. Let's have a look
Let's see how this feels now.
It feels like it's biting it. Once again, we're not trying to crank this in because we don't want to spread that thing out. Now, what we're going to do is we're going to turn this nut down and we're going to cross our fingers that it's going to pull that baby out of there. It kind of feels like it might be working. It's not pulling the bolt out. That wasn't so difficult, now was it, gang? There she is. Look at her. Piece of cake. There's our sludge trap. Now, we're not going to reinstall this because this all needs to get cleaned very nicely but when you are reinstalling, you want to pay very particular attention to that whole lining up with where we took this out.
Because if it's caddywhompus in the hole like that, that's going to hit that and it's going to crunch that. It's not going to work out right. As you can see, there's a lot of people saying oh that's a really tough job, and that really sucks, and that's really hard. That only took less than five minutes. We're good. Let's move on to some other jobs we got going on here today. We need to remove the rocker shafts from the rocker boxes. These little go with the rest of the parts for the vapor blaster. I'll show you a really easy way to do this where you don't damage anything. I just use this, a center punch in that end of that where the hole is where the oil feeds.
I’ve done it this way multiple times, it’s never hurt anything because you don't really want to hit on this with a hammer. I guess, you could use a rubber hammer but sometimes they get stuck in the middle so this works real well. You've got your rocker arms rockers in here and there's some Thackeray washers. We'll see how that works when it goes back together, I can show you when I get it out of here. There's also an O-ring seal on this and it does need to replace. Even if you're just doing a top end, you still want to remove these. I'm just going to get that on there and lightly tap it out.
There you can see the seal, oil seal, O-ring. If you have oil leaking out of the end of this little thing here on your motor ,it's pretty good indication that that O-ring is failed. Let's see what I mean. This one's being a little stubborn. There she goes. There's your rocker shaft and you're also going to inspect these for wear. They don't generally wear unless something's wrong. That's not too bad, that looks pretty good. You can also put the other -- some bushings on these and then you could just come in here. Actually, it's easier if you take these off, your rocker caps where you'd be checking your valve adjustments.
Then, you can just slide this out of here and then you've got an arrangement of washers and springs and such. I'd take this one out and you may notice now you've got three washers that have a larger diameter and one washer with a smaller diameter. The smaller diameter washer is going to be on this side when it goes back together. A lot of times, that's going to be on this side so that one -- a lot of times, I’ll just take this stuff and stick it back on here for safekeeping. That's a nice fit. No problem there. Nice and tight. Since these are going to get blasted, I’ll go ahead and take the rest of this hardware off of here. If you're reusing this stuff, make sure you bag and tag it. We got these two keepers.
These parts right here are kind of important and I’ll show you why. You'll see how this has a serrated edge and you’ll see on this there's that little titty there. When this is on here and you tighten this down, it gets to that and it keeps these from loosening and falling off while you're going down the road. These are kind of important, if you don't have any you should have some on there.
Once again because of wear patterns and such, I’ll put these in a bag now, in a ziplock bag and I’ll put a little piece of paper in there and denote front or rear on the rocker box. When these are cleaned up and ready to go back together, these parts will go back in this rocker box. I won't put this part and this one because it didn't come out of this one. Piece of cake. We're going backwards this time. We're taking these off first instead of last. We'll keep that one here. We'll go ahead and grab another towel.
There we go. Disassembled. Once again, going to check for wear. Put this back on there. If you feel any movement side to side, that's a good indication that something's worn or it may need replaced. You also want to look at these, tips of these that's what engages your pushrod and you're going to look at these that's your valve adjustment that one rides against your the tip of the valve. That's where you do your adjustment through the hole.
All right, now that that's done, we'll take some valves out of our cylinder head. Here's our cylinder head. You may notice here, this side looks relatively clean, this side does not. That's probably an indication that a valve guide is letting oil leak pass the guide in between the guide to the head fit. You know, anytime I do rebuild an engine, I don't just assume these things are going to work right. I want to disassemble every single last piece in part.
We'll take the valves out. The other thing you want to look at and maybe making your determination if you're going to replace the valves or reuse them is the rocker boxes. We just took apart the piece that contacts this and opens and closes the valve as it goes as the pushrods go up and down. If these are really, really worn where they've got a big cup on these tips where it touches, sometimes they can -- it's common practice in automotive to grind that.
If they're really, really worn, it's probably better off just to put in each set of valves in there. We have this valve spring compressor available. I personally like to clamp it in the vise, makes working with it a lot easier. You're going to turn it all the way down. This portion of the tool is going to be in the middle of the valve, while this portion of the tool is going to push the top collar down so we can get the keepers out. We can be able to get the tool in there it looks like I want a little bit more than I should have, but that's okay. We'll just turn this one up a bit and then we'll turn this one down. When this gets to the top collar, you want to kind of make sure it's centered on there. See how it likes to walk around a little bit?
You hear that?
Not yet. There she goes. she's been together for a while. I'm compressing the spring. Now, you can see the keepers right there. I'm just going to use a magnet. There's one, there's the other one. I'm going to release the tension. Looks like I was darn near coil bound there. Take your springs, you get the top collar. Give an innerspring and an outer spring and then you have a bottom collar. There she goes. Now, with these I just always put things back the way they came. Look at this. This is very interesting, here. I'll show you this and you're just going to slide the valve out of there. See that? That guy looks real oily. That's on the same side that looks kind of discolored.
Then, there's also a fit that you're concerned with here. Basically the fit -- the outside diameter of this versus the inside diameter of the guide is your valve to guide clearance. I'll be replacing the guides on this and probably the valves, too, by the looks of this valve. Then, you're going to install the new guides and then they'll be reamed to fit so that you have the correct running clearance. It's too tight, they'll gall up. If it's too loose, they'll wear prematurely. The other thing I usually do, regardless of whether I'm going to use these or not, let's just say your valves look like they were in pretty good shape you might want to reuse them.
It's a good idea to keep track of where they came from. Once again, wear patterns. This is going to be the -- I just make a piece of paper here and this is -- anytime you're doing right or left on a motorcycle, that's concerning you're sitting on the bike. This is the left, this is the right. This is the right exhaust, right exhaust. I'm just going to pop this stuff in a bag here, the valve, all the pieces and the keepers like so. We'll go ahead and take another one out. You'll get a close-up of that so you can see what's going on over here.
Once again, all of our associated parts and we are going to be reusing the collars. Anytime you're taking stuff apart, it's a good idea to keep track of it. Don't just throw it all in a big pile and then when it's time to put it back together, you're looking for one of these little keepers. Now,` see how that one's very clean and nice looking where the other one looks really crappy. Yes, it looks like we had an issue going on there. Two more to go.
One seems to be stuck in the groove. There, she just fell right out. Spent a little bit of oil on it. That particular valve, the first one we took out was stuck in there because all that crud. Notice how this one's just falling out. It's probably not a bad idea to -- as you're removing it from the tool, just put your finger on the bottom of it. See how it just wants to come right out of there? That's going to be our eye. Last one. Pushing the spring down to reveal the last two keepers. There they go. There you have it. What we're going to do now, remove that hose. I'm going to leave these on for blasting.
Sometimes these are real easy to come off and sometimes they're not. As you can see by looking at that particular seat, that valve was not seating. See, if you look at that, you can see how there's a defined line there you can see where that one was seating, you can see where that one was. There was an issue with that one and I would bet that's the one. Yes, that has the crud around it. She was definitely due for a valve job. When you guys weren't looking, I also removed the bearings from the inner tranny. This is the lay shaft bearing. It was in this hole and this is the main shaft bearing. I just heated these up.
This one drives out from this side, comes out that way. The other one comes either way. It doesn't matter whichever way, there's less material showing. These are the parts that are going to go to the vapor blaster along with the crankcase. Anytime I'm doing these engines, I like to vapor blast these parts. There's just really no way in my garage to make this as clean as I can get it. We're going to take a little field trip to the vapor blaster. You guys want to come along? It'll be fun.