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I decided to build up my spare engine

3K views 53 replies 9 participants last post by  King_Panther13 
#1 ·
I created a thread about this a few weeks ago, asking if I should use my spare engine for parts and build up my current engine, or build up the spare and then just swap. While it'd be most logical to just build mine up, I decided that the most convenient option will be to just build up the spare, as everything that it needs done to it is something I would do to my current engine anyhow.



Now, I want to know if I have the right idea of what all to do with it. I want to make it as perfect as I can. I know that these engines don't take kindly to modding, so unless I find some easy mods that have little risk to negatively affecting my performance, it'll be a stock rebuild.



So far, my list of things to do/get is:



Gasket Kit

Mechanical Seal

G8 Stator

Cam Chain+Tensioner

Piston Rings

Lap Valves

Inspect entire engine, and decoke everything possible.

Clean out and/or replace oil pump

New clutch kit, if current one isn't serviceable





Is there anything else that I should consider, or did I pretty much nail everything?



Oh, and there was a bit of rusty water that came out of the cooling pipes when I removed the radiator. I was told that this can be flushed out after the engine is rebuilt, and put back on the bike. Is this true, or can I get it flushed out before putting it on the bike, so I can get it "perfect?"



Thanks for the advice. This is still a bit off in the future...but the first thing I'm going to do is get the heads serviced (the valve lapping and whatnot) and get my gasket kits. Then I'll slowly do everything else until it's ready.
 
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#44 ·
Well glad they came off for you, and as for the "screwdriver hump" I too have done that, and as long as it doesnt span the entire width of the gasket area you should be ok just smoothing it down. The "cheesegrater" gasket you found is the "normal" head gasket, as all head gaskets I have ever worked with have metal in them, if only a metal disk around the cylinder opening. I myself would NEVER use a gasket without metal in it on a head as normal gasket material will not be able to survive with the pressures involved. You will find when you put new gaskets in the WILL have metal in them, as that is the part that actually "seals" the head joint (act as giant crush washers).



You will probabaly have a "carbon ring" on the inside of the cylinder right at the top, best to leave it alone. Every shop manual I have ever read has stated to "DO NOT REMOVE" this, as it apparently helps with head sealing and combustion (not really sure why, as if you hone the cyclinder its the first thing to go, as it is if you remove a piston). You can remove major carbon chunks from the top of the piston if there is any, but unless its large chunks (carbon film buildup) it wont hurt anything. As for the heads, you can clean them up with a wire brush (or like i do, with a wire wheel in a drill or drillpress). I would recommend getting new valve seals (usually come with a complete gasket set, or you can buy them seperatly, you need 8) and lapping the valves. It sounds complicated but is actually fairly simple. The big trick is removing the valves, for which I would recommend you buy a valve spring compressor (small one, not the big ones for cars as they wont fit). You can do it without, but I wouldnt recommend it as its a pain to get them back with a compressor, almost impossible without. For lapping you just need a lapping tool (wooden dowel with a suction cup at each end, abot $2.00 at an auto store) and some lapping compound (can use pollishing pummice if in a bind, its basically fine sand in a paste form, most auto places sell it). Then you just put the compound on the valve seat in the head, drop the valve in place as spin it like your making fire lol. Once you see the "lapping haze" on the valve seat go all the way around, your done.



NOTE ***** You MUST make sure you mark EACH VALVE, ITS SPRING AND CAPTURE BITS AS A SET. Do not mix up any of the parts as they MUST stay as a set AND>>> AND >>>>AND go back in the EXACT HEAD AND LOCATION. I know some may say "as long as the exhaust valve goes in and exhaust spot its OK" ..... ITS NOT. Each valve MUST go back where it came from or you WILL end up with oil leaks and probabaly rapid wear of the valve guides (something you REALLY dont want to change)



OK, now not meaning to scare you, but its better to get a little freaked out BEFORE you remove them then after when you cant remember what went where. I marked the heads (L&R) and numbered the valve spots on the head (1EL, 2EL, 1IL, 2IL and similar for right) and kept each valve and its "bits" in a seperate plastic bag with the same markings. Also (after cleaning the valves) marked the valve faces.



What you will find (I did) is that with the valves lapped and new valve oil seals in place, the engine runs a lot smoother and "peppier" when set up. If you need any help with the process, we are all here to help. When its all said and done you will find the hardest part is keeping all the bits together and marked for the right spots
 
#45 ·
Hmm, it was suggested to me by Mr. "You must do the piston rings!!!" that I should just bring the heads to an auto shop and have them lap them. That may make things a bit easier, depending on the price. He said that when he did it it "didn't cost much" but it was so long ago he doesn't remember the price. If it's overly expensive, I'll buy the stick and do it myself. For something like this, I want to ensure that its being done properly and as good as it can be done. I'll get the valve seals when I pony up the cash for my complete gasket set. I'm not in any hurry to do this, and it may be a few weeks until I do something to the engine again.



I heard that some kind of pin or ring or something was supposed to be swapped or switched to make setting the tappets easier in the future. Could you point out on the diagram what it is, so I don't mess with the wrong piece?



Oh, and as promised, I took some pics...but it's dark now so I wasn't able to get the very best shots of the cylinders, but I think that the shots of the heads are more than adequate:















 
#46 ·
I was tooling around for gasket kits....found this kit here for a LOT cheaper than the ones recommended to me. It seems like it doesn't have the rear cover gasket in it, and probably is missing other things that I can't quite spot...however, Buying this rear cover and that kit would save me a lot of cash.



That just boils down to...what out of that top end kit is missing that a normal "full" kit would have? Other than rear+front cover gaskets, which seem like they can be very easily sourced for less than the price of buying a full kit.



I'm really cheap. Well, rather, really broke...lol. The sooner I get the gaskets the sooner I can move on to buying other things. If only my hours would pick up, I'd be fine. To think I tell my job I'm willing to work every day over the summer, and they respond by giving me LESS hours!
 
#47 ·
The kit you show seems to have all important ones you may need, depending on what you are actually taking apart. It has the head gaskets and valve stem seals (most important ones) but lacks the front, rear gaskets, as well at the ones for the timing unit (advancer thing lol). I know you can pick up back and front gaskets seperatly (back FOR SURE must be a proper gasket while some of the others can be made).



The heads and cylinders actually look really good. I would check to see how much "didnt cost much" equates to actual dollars lol It is not a really hard job, lapping is VERY easy, with the hardest part being "putting the springs back on". Cost wise, you will save doing it yourself, about $2.00 for the lapping tool, $2.00 for the lapping compound (unless you know a mechanic that can give you a "dolop") and amybe about $10-$25.00 for the valve spring compressor. (mine cost $15.00). Lapping is easy, and doesnt look like your valves will need much. you simply spin the valve back and forth and check the "haze" left on the valve seat and valve face. when the entire "seating" area is "hazed" ( basically like frosted glas as opposed to shinny metal) you are done.



This also allows you to check the valve stem clearance (the amount of sideways wiggle the valve has in its guide). If it is within spec your good to go, if they are way to loose it means new valve guide which are a pain (they are press fit sleeves). With the valves lapped and new valve stem seals yur heads will be good for a lont time.



Just remember, EACH valve MUST stay with its HEAD/HOLE as well as all its bits (keepers and springs). This is because each valve seat will be a little different and the wear on each guide/stem will also be different. Mixing them up can prevent valves from seating properly, burnig oil due to guide slop, and very poor performance. Best money you will spend doing this is 8 zip lock bags and a sharpie marker.
 
#48 ·
I think I need pretty much every gasket...I mean, I'm doing a complete overhaul, save for the crankshaft/piston/etc. It just seems like paying 38 for the head gaskets and whatnot, and then 10-15 (after shipping) for the rear/front cover gaskets will be a lot cheaper than paying 80 bucks and shipping for a complete kit. Though, upon thinking about it a bit more..not really *too* much cheaper. So maybe I'll wait till I can scrounge up the 80 bucks.



As for storing the bits and pieces, I'll probably use pill bottles, or old plastic bottles or something. Toldja I'm cheap
. My uncle who told me that it "doesn't cost much" to get the valves lapped and seated by a shop has a valve spring compressor that he'd let me borrow...so if I call that auto shop and it turns out to be too expensive, then I'll probably be able to lap the valves for 5 bucks. I'd probably be willing to spend 20-40 bucks to get them lapped just because it'd be less of a pain, but then comes the whole money issue...I could save that cash and do it myself, and be that much closer to my gaskets and all of the other bits and pieces.



And it's great that they look good to you guys. I didn't think they looked bad as much as I thought that they looked dirty. The only thing that concerns me is the rust/orange gunk in the ring around the piston...or I guess the "moat" around it would be a better term. But that's part of the cooling system I think, so that'll probably get flushed out when I run vinegar and stuff through it.
 
#49 ·
Well, if you can get a shop to lap them for $40.00 I would jump at it. I have a mechanic who is a good friend, and they normally charge about $200-$300 (whihc I could get for 1/2 price, but im cheap too lol).



Dont get me wrong, sometimes it better to have a professional do things (like grinding a crank or milling a head surface) but sometime you can do an even better job yourself. The main reason is YOU CARE about your bike, to them its just a valve job. You also have total control over the work doing it yourself, not if you take it in (and YES, I have watched mechanics do valve.... pull them.... thow everything into one box.... clean them and put it back together. When I asked about "matching them" the response was "they are all the same, and if it does cause a problem it wont show for thousands of miles". No, never took anything there, was just in their doing sprinkler pipe work).



As for the "rusty void", that is the water jacket which is usually full of coolant. You can usually pull most of the crap out or leave it and let a good flush clean it out. I myself clean the crud out the best I can, but prep it first. I will run a heat gun over it until everything in there is completely dried out, then using a welding rod break the big crap loose WHILE holding a good shop vac up to it. That way anything that breaks loose gets sucked up and not dropped in. You may want to use the shop vac first before heating for two reasons. first it gets already loose stuff out, and second there is a good chance the vac will pull some pooled coolant up and out (startled me the first time I did it, then have to dry it again).
 
#51 ·
Well, if you can get a shop to lap them for $40.00 I would jump at it. I have a mechanic who is a good friend, and they normally charge about $200-$300 (whihc I could get for 1/2 price, but im cheap too lol).


With friends like that..... No honest machine shop would charge more than 50 bucks to lap the valves. If there is a major rework needed, such as re-grinding, new seats, whatever, they'll usually charge the hourly shop rate (around $100 an hour here.) There's not much to it and not much specialized knowledge involved, if you can sweep a floor, you have the necessary skill set to lap some valves.
 
#50 ·
lapping the valves is a pleasure.very easy to do,and quite satisfying.i would not pay 10 bucks for someone to do that for me.


my heads on my good running 82 were pretty nasty,but,they cleaned up fine.











good luck on the rebuild Cramer
 
#52 ·
i think lapping the valves are one of the jobs.....you simply cant do wrong..they wont let you.Snr. Stern,i think the pices you quoted were not for lapping,maybe reseating or some other machine work
 
#53 ·
Yep, but you some shops (and as I said I would never take anything to this place, most were kneckle dragger with an IQ of 2 over the min to be able to breath) see a guy with heads in his hand and they figure "I can soak him" I also agree with bandit, I find it quite nice to do them myself, leaves you with a real "I accomplised something that wasnt just cleaning" feeling
 
#54 ·
For those that are/were following this thread, I decided to consolidate it all over to this thread over here, as now the goal is to get tihs spare engine up and running as soon as possible since my current engine just can't be trusted.



I just got the rear cover off, and now I'm trying to find the best deal on a gasket kit.
 
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