1983 B&S Flathead (130200 series) Breakdown/Rebuild

[LeeMajors]

Hi Lee.

I ran into the same issue of how to plug the hole for the governor crank (as it is called). Read that some do utilize the crank rod or use JB Weld or some High Temp RTV sealant either alone or in conjunction with the rod to plug the hole.

I decided to tap the hole for a 1/4" machine screw and sealed the threads with Permatex High Temperature Thread Sealant. Says it's resistant to 400°F. Some of it oozed out around the flat washer I used--it's the white substance. The screw is only 1 1/4" LOA so it doesn't protrude into the crankcase.

I used a 1/4 NC20 tap.

Thx for this man ^^^ I was considering tapping it also and after seeing yours I just might go that route? It just looks so much cleaner that way. Great job on that, it looks amazing! Just out of curiosity; did you paint that yourself and if so what type of paint is that? It looks REALLY good man! I finished painting/curing mine a few days ago and just haven't had a chance to UL the pics. Anyway, Thank you again for the pics and the reply, you really just helped me make my decision.

 

[Hellion]

Thx for this man ^^^ I was considering tapping it also and after seeing yours I just might go that route? It just looks so much cleaner that way. Great job on that, it looks amazing! Just out of curiosity; did you paint that yourself and if so what type of paint is that? It looks REALLY good man! I finished painting/curing mine a few days ago and just haven't had a chance to UL the pics. Anyway, Thank you again for the pics and the reply, you really just helped me make my decision.

If I didn't enjoy tapping threads so much, I may not have done it.
I wanted an honest mechanical seal first and foremost. I was worried about an RTV or Epoxy plug falling out inside the engine or getting blown out, especially working itself loose if the metal was weeping grease and oil out if its pores. Part of the effort was looking for a suitable screw and I was checking every jar of nuts and bolts on hand.

I had the block all stripped down completely but not polished like yours. Instead of power sanding or wire-wheeling all the old paint off, I used Goof Off Pro Stripper aerosol and scraped it off with a plastic putty knife. But yes, I painted it myself with Rust-Oleum paints. I used Self Etching Primer #249322 and Semi-Gloss Protective Enamel #284378 for the top coat. I could've gone all crazy with different colors but I basically tried to replicate the OEM color.

I'm gambling that the paints will hold up to the engine's heat.

EDIT: Disregard the tap I used. I had a thread gauge that I used along with the tap to match the threads of the machine screw I found. Whatever you find to plug your "governor hole" will or can be different. One of the first things I found was a hex head bolt but it interfered with the irregular surface around the hole. I did a lot of fiddling with this minuscule part...

 

[LeeMajors]

So I finally have a chance to get some of these pics UL'd. Please forgive the quality I've been having major camera issues lately. Also I'll do my best to keep these in order but at this point I just want them off my HDD so they may be a little sporadic..?

These are mostly pics of my painting/curing process and some reassembly. Oh and me making a spring compressor out of an old "C" clamp I had, cause... well let's face it I'm a cheap sob.

Also 2 quick notes; the ARP assembly lube... that was ONLY used for the con-rod bolts. The rest of the parts got Permatex Ultra Slick (the red stuff). And I couldn't find the right size tap for the governor bushing so I wound up using High Temp RTV along with the modified flapper-shaft-thingy for the time being. Anywho, here they are:

 

[LeeMajors]

^^^ pics cont...

 

[LeeMajors]

^^^ and some more pics...

Btw, made the spring compressor by using a cut off wheel on an angle grinder to get the bulk off and then a grinding disk for the rest. The disk was the perfect thickness for the valve relief cut out. And then at the end I went over it with a 80grit flapper disk just to remove any sharp edges.

 

[LeeMajors]

^^^ still more pics...
Note that on my crankshaft I don't have the normal "DOT" to indicate the proper timing position, for some reason mine has a "LINE" instead? At any rate, for anyone who may not know, your goal when assembling these two parts is to align the mark (the line in my case) on the crankshaft with the mark (should be a dot) on the cam to ensure proper timing position of the valves and piston during rotation.


Still a lot more to come so stay tuned!... if you're into this kind of thing, I mean?

 

[LeeMajors]

So there's still quite a bit on my list of things to do, one of which is making gaskets. I plan to use this rubber fiber sheet which is great for timing covers, diff covers, fuel pumps, etc... it's oil and fuel resistant so it'll be perfect for the side cover. And you can pick it up for less than $10 at any autoparts place.

Also the pull starter gear... are these supposed to Rattle? Mine sounds like a baby rattle!!? The gears work fine but it absolutely sounds like a baby rattle when I shake it around!?... so I'm guessing all the bearings are rolling around loose in there? Should I replace that? Or does it not matter? Can I use it till I can get another one? If anybody can touch on that I'd appreciate it?

Oh! And I almost forgot about the carb pics! I still need some parts for it but I'm pretty sure I can get them and my gas cap locally? And speaking of gas caps... what a BEAR it was to get the rust out of that TANK!!!? I used the old cider vinegar trick and it worked pretty good but a majority of what I THOUGHT was rust was actually fudged up gasoline that must have sat in the tank for ages and made a whole new kind of mess inside it.

I really want to mod this breather valve. Does anyone of you have some solid experience with this? I'm a firm believer in not caring AT ALL about emissions and I absolutely refuse to recirculate power theiving crankcase gasses, full of oil, back into my air intake/carburetor on ANY of my combustion engines (for obvious reasons)! So have any of you modified this on your own engine, with any degree of success, and if so could you plz enlighten me as to how exactly you went about it? I've been researching it pretty extensively but haven't found any clear concise examples of how it was done and what worked best. It seems most that have molded it just wound up with oil spraying everywhere?

Lastly, I'm making this post directly from my phone so I'm not sure how these pics will be sized? I apologize if they're REALLY big or REALLY small.

 

[mckutzy]

Wow thats pretty nice.....looks great
Ya the starter nut, has a few bearings and ramped surfaces... hence how it engages and disengages.....
You will most likely need the tool to tighten that nut properly as it is awkwardly shaped to use anything else.

 

[LeeMajors]

Couple valve lashing pics...
Intake clearance = .005in - .007in
Exhaust clearance = .009in - .011in
I went right in middle on both, so .010 for the exhaust and .006 on the intake. And as you can see in the pics i had to use 2 feeler gauges on the exhaust to get .010in (just in case you didn't know you could do that?..you can.)

 

[Hellion]

Wow, some great photos here which just show basic detail. Some may yawn at all this but it serves to tell the whole story about reassembling this classic engine. Hopefully it guides many through the process in the future.

Are you going to lap the flywheel to the crankshaft?

If you haven't disassembled your starter clutch, I would just to inspect and clean it. Should be six balls in there but I have heard that it will still function with less. The recesses inside as well as the ratchet should be clean with no lubricant added in and around the ball area.

 

[LeeMajors]

Wow, some great photos here which just show basic detail. Some may yawn at all this but it serves to tell the whole story about reassembling this classic engine. Hopefully it guides many through the process in the future.

Are you going to lap the flywheel to the crankshaft?

If you haven't disassembled your starter clutch, I would just to inspect and clean it. Should be six balls in there but I have heard that it will still function with less. The recesses inside as well as the ratchet should be clean with no lubricant added in and around the ball area.

First, just wanted to say thank you. I appreciate your appreciation sir! lol! Seriously though I really do. And the reason I do take so many pics is for just the reason you touched on, so that hopefully it helps the next guy that does some work on one of these. With all of the racing and competition involved with karting I think that many of the builders opt to not show folks what they're doing (or how they do it) to up the power. And I think when more people realize how easy it is to modify engines to increase performance that it will slowly change the market. Custom made parts are one thing entirely, but "builders" charge absurd amounts of money for engines that you or I could build at home. I mean I've seen some built Raptor engines going for upwards of $1500+ and that's just crazy to me!? My point is: that's why I do build threads. To show ppl that the Easter Bunny isn't real. And that there's NO REASON anyone should be paying that kind of money to a man, no different from themselves, to do work that they could do themselves. Now don't get me wrong; if you have money like that, then have at it, if you so choose? But that's simply not a luxury I can afford. And the same goes for cars, these so called tuners and engine builders are charging ppl crazy amounts of money because the average person doesn't know any better! And they think that what these guys do is beyond them. Anyway... I'm ranting. So yea I'm probably boring ppl to death with all my pics but for every 100 dead ppl maybe I can get lucky and save 1? Or be fortunate enough to have a Hellion that can appreciate the little things..? Either way at least somebody can dig it.

And then I wanted to ask you what exactly ^^^ that means? How does one "lap the flywheel to the crankshaft"? I ask because I've never heard of this but if it's something I'm supposed to do then I definitely want to do it...?

 

[Hellion]

And then I wanted to ask you what exactly ^^^ that means? How does one "lap the flywheel to the crankshaft"? I ask because I've never heard of this but if it's something I'm supposed to do then I definitely want to do it...?

Lapping the flywheel is what many in the go kart tuner crowd do to enhance the fit of the flywheel to the crankshaft. You're grinding the taper of both pieces to match uniformly and precisely to each other. It ensures the flywheel runs true with little to no wobble.

With the way the shaft and the flywheel come from the factory, there's manufacturing variances, tool and casting marks and other "artifacts" ("grain" and other textures, esp in cast iron) left behind that don't allow the two materials (either aluminum and steel or cast iron and steel) to form a good bond.

Also, what I understand is paramount to the whole procedure is that it results in a fit so tight that it eliminates the need for a flywheel key. You are free to advance or retard the timing in an infinite amount of ways provided of course that the flywheel nut/starter clutch is torqued to specification; I think it's 55 ft lbs.

>>> Mckutzy mentioned having that special B&S tool to tighten and loosen the starter clutch/nut but I got a 16" pair of channel lock pliers for that job. I padded the jaws with corrugated cardboard and duct tape and once I put it all back together I will just tighten the clutch "pretty tight" and be done with it.

 

[mckutzy]

You can use those to tighten/ remove the nut... But a potential damage could occure(just sayin)
Here's the nut spanner tool...

There is another tool, that holds the fly wheel, by the fins...it's meant as to not damage the fins from a screwdriver...

 

[LeeMajors]

Okay, thanks fellas! This is great i never even thought about the variances in the machining on those 2 parts but now that you said it, it almost seems obvious!? Would I lap them in the same way I lapped the valves? Like with a lapping compound and just rotating the flywheel back and forth on the crankshaft?

 

[Hellion]

Okay, thanks fellas! This is great i never even thought about the variances in the machining on those 2 parts but now that you said it, it almost seems obvious!? Would I lap them in the same way I lapped the valves? Like with a lapping compound and just rotating the flywheel back and forth on the crankshaft?

I didn't think about it either until just recently when someone here posted an ARC Racing video on how to install one of their billet flywheels (they make one for the flathead, you know--hint, hint). Here's the video--skip to 6:30 where he starts in on the lapping procedure:

https://www.youtube.com/watch?v=7JbNzoUjpFw

And yes, you lap the flywheel like a valve taking precautions so to avoid lapping it in the same spot over and over (he goes back and forth on one area of the shaft, then lifts the flywheel away from the shaft, rotates the f'wheel 1/4 turn or so then re-engages the shaft and resumes the back n' forth motion. Wash, rinse and repeat).

EDIT: Actually he didn't do it the way I described.

 

[chancer]

Thanks for posting that Hellion, that is a VERY good Video.
and thanks to ARC for making it.

 

[LeeMajors]

Quick question gentlemen.... can one of you plz explain to me exactly where this wire goes and what it's function is, how it works, etc..etc..? Thx in advance.

Sorry for the sideways pic I'm uploading directly from my phone

 

[mckutzy]

That's the dirt screen... The starter sits higher than a clone, it only interacts with the starter shaft(the square shaft), so there is a significant gap... On lawn mowers this would quickly fill with dirt and grass, being sucked into the engine spaces via the suction of the flywheel fins.

 

[Poboy kartman]

That's the dirt screen... The starter sits higher than a clone, it only interacts with the starter shaft(the square shaft), so there is a significant gap... On lawn mowers this would quickly fill with dirt and grass, being sucked into the engine spaces via the suction of the flywheel fins.

Look again...he's talking about the brown electrical wire.

If I see what I think I see..it's a kill switch wire..and used to be hooked to the throttle plate so it made contact when the throttle was all the way closed....you can hook up a switch and hook it to ground for w kill switch.

 

[mckutzy]

Oh hahah..... I see it now....... I was on the phone, just got up and replied.......
It looked like he was refering to the screen.....