Vintage Karting Forum

I was able to find most of this thanks to Dave and Brian.

I'm going to document the slow rebuild process of some Homelite KR82 engines. Fortunately, these engines don't require a great deal of skill to rebuild. If you have some common tools, a press, heat gun, and internet, you'll do just fine.
 
This is what the final product should really look like. I'm going to take a few liberties and deviate from the factory perfect route i.e., fasteners and paint color.



I've done KL100's, KL92's, hybrid KR95's, among others. Below are my only two HL 82cc blocks. The part casting number 56694 is shown. The actual part number from the IPL is A-56714.




Here are the bare blocks after powdercoat. After blasting I use the high-temp tape (PET) to mask off the gasket mating surfaces.



See the bushing and roll-pin slot? It's a good idea to replace the bushings. Every HL engine I've done has an unacceptable amount of wear.
 
Fastenal has the bushings and the pn is 0434810. You'll have to groove the outside to fit the roll pin. I used a ball-mill to slot the bushing. Anything which can make a similar slot will work. Press a new 3/32 X 5/16" roll pin in to keep it from spinning in the block.



The bushing is a few thou too big from Fastenal. There has been lots of talk about grinding bushings and this may or may not clarify anything?

This type of bushing will crush proportional to the bore they are pressed in. Without modification, the new bushing from Fastenal is too tight around the crank.

You can't mess with the bushing bore, so you need to turn the outside down to get the proper crush. I found by making the OD around .874 worked fine. It was a light press fit in the block and was perfect for the crank. Waaaay better than the wallard out bushings in the used blocks.



At this point you can check the crank fit on the bushing.

If it's too tight, then press the bushing out and take another .001" off of the OD of the bushing.



Freshly burnished crank and new bearing. Snap ring in place.

You'll never find these cranks by looking for the 56423-A (right) or 56810 (left) part number. With that said, the 82 cranks are very common in the early saws. They had no counterweights and a 1.50" stroke.

The bearing part number is Nachi 56097. The metal shield is on the outside of the crank.



Some of the blocks can be really rough if water was left to sit inside. In the race to make saws lighter, Homelite used magnesium for the blocks, manifolds, and shrouds. This block in in great shape.



I made some "gasket-crankcase sealing" (55048-A) for the block. These are still available from the vintage saw collectors. If you have gasket material in the .020 range and a gasket cutter, make them yourself. The OD is just over 1.55" and the ID is about .800".



Heat the bearing pocket in the block with a heat gun. When it get's around 200F+ it's ready for the crank assembly. It will push right in with almost no pressure. With the bearing fully seated, the groove will be aligned for the retaining washers. If you mess this part up, then press the crank out and redo.

Crank fully seated.



On the topic of crank retention. Homelite had to use a low-profile screw so the counterweights would clear. It's called a "cheese head" screw. They are more commonly found in the U.K. for some reason.

Here is a used and a NOS screw.



They also use a serrated lockwasher to engage the bearing groove. Use the thin 1/4 lockwasher for the crank. The thick LW is for the cylinder and other 1/4 bolts.

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After the blocks cool, check the crank to make sure it spins freely.



Ordinarily the 82s were painted Homelite blue. The aluminum recoil adapter would've been painted with the shroud assembly. Again, I'm slightly deviating from the original build.

The decals are available from "Sign Time" in Visalia, CA for about $12/ea.



HL intake and no stuffer. See the space left between the manifold and the block? It needs something here to take up the volume of the intake track.



This is an aftermarket stuffer I found in one of the engines. It's cut from rubber and is in great shape. I've also seen them made from aluminum. I'm sure any epoxy filler will work as well. There is no mention of a stuffer in the IPL.



The KR82 timing plate has 55416-A cast into it. The brass post sticking up is for the points.



The small journal cranks take (2) SKF 6105 seals. They are very thin and unforgiving. They sit Siamese with the lips facing out on either side.

I find it easier to press the bearing side seal first.



Then press the other seal in. It doesn't appear to matter if they seat against each other, or with a small gap between them.



Find some quality GBH1012 bearings. Theses are for for the small journal/small bearing timing covers.



Heat the timing plate with the heat gun until reaching about 200F+. Press the bearing in until it seats in the pocket. You should be able to see the chamfer cut on the cover when it's seated correctly.

We will change gears for a second and look at the differences in ignition and points boxes.
 
The very early HL kart engines and some saws had a WICO unit. Everything else (karting) used the R.E. Phelon (REPCO).
 
I'll only show the Phelon since they are going to be more common.
HL saws were either direct drive or gear drive. Based on the drive type it would change the drive rotation of the engine. HL took advantage of this feature and made LH and RH kart engines.
 
The main difference between the LH and RH engines is the crank grind for the points and the direction of the flywheel fins. The shroud and head cover help determine what you're looking at, but not always. One of the R82 blocks I'm working on here had a newer large journal RH crank, LH flywheel and cover. It all worked fine because the points were removed and it used a transistor ignition.
 
Common LH and RH side timing plates respectively. These are just 2 of the several types out there. The LH one here (57576) would work for a KL95/100. They have no brass post and a larger bearing pocket. The RH (55416 A or B) will work for R82/92. They have the brass post and a small bearing pocket.



Below is an unrestored LH timing plate for the KL82/92. Notice the large casting number (55957A) and the brass points post. This would be the most correct timing plate for the 92 and earlier.



Points boxes. There are many types with just subtle part number changes, but they all have the same bolt pattern and coil mount angle. The functional difference is whether or not they have the hole for the brass post.
 
I use the one on the left for timing plates with no post. The one on the right I use for plates with a post. The small hole to the 7 o'clock position of the crank hole is where the points mount.



Here is an example of the 2 main points types.
 
Newer 1-piece points like KL95/100 and some other hybrids I'm working on.



The older style 82/92 with 2-piece points on the brass post.



With coil mounted and points loosely in place.



Rods..
Homelite rods are cheap and available everywhere. Maybe these engines never made enough power to stress the rod?
 
HL used a B78 top bearing pressed into the rod. They are copper plated to maintain a tough beam during the bearing surface carburization. The lower end has bonded phenolic "thrust washers", and a cracked cap.
 
I call these the small journal rods. They are found on all of the kart engines without exception. They have 55002-W stamped into the beam. They take 27 needles in the bottom end.



The top rod is from the 770/775 and Super Wiz 80. A-58303-B, A-58303

It has the same top bearing as the kart rods, but takes 31 bearings on the crank. The MC rod bolts work well for these. To use this rod you need to find the right crank and scallop the block. 



Needle bearings are available all day. They are held together with wax which needs to be melted off and thoroughly cleaned.

Cranks..
This is where things get fuzzy for me because the stamped number on the counterweight means almost nothing when trying to figure out what you're looking at.
 
Here are half of the cranks I have to work with. Based on appearance only, these are the either kart cranks, or the exact same crank used in a saw, or saw cranks only.

Karts had 1.50"/1.54"/1.60" stroke cranks. The 1.54" was used to stroke an 82/92, or came in the KL95 which had a different FW side bearing journal.



Here are 2 770D/775D large rod journal cranks. They are right hand drive and have 1.54" stroke. They never came in kart engines. Additionally, the FW bearing journal is large 11/16", and the counterweight has a fillet.



When building a Homelite I had to ask:
--Which direction do I want it to turn LH, or RH?
--What is the stroke?
--What journal sizes does it have?
--Does it have the additional counter weights?
--Does the FW end have a fillet?
--What size FW does it take?

All 3 of these cranks have 1.5" stroke and RH drive. The far left is from a Zip saw and uses a larger FW side bearing. It would work find in an R82/R92 with the appropriate timing plate.
The 2 on the right would be the most correct for an R82 only. 



Before I move on, I just want to show you how to tell if it's a LH or RH crank. With the rod journal at 12 o'clock look at the points cam.

LH crank.



RH crank. Keyway it too worn to use as-is.




The 2 types of cranks have either 7/16-20 or 3/8-24 threads on the FW end.



Important edit. I've tried to track down some saw part numbers. Remember we can't use the G cranks or the SW80.


Crank PTO steps down 9/16, 7/16, 3/8.

700G crankshaft A-57473
700D crankshaft is 56098-C
707G crankshaft A-57541
707D crankshaft A-57546
770G crankshaft  A-57541-B or A-57538-B
770D crankshaft A-57546-A
775D crankshaft A-58899
Super Wiz 80 crankshaft A-58892-B

HL made a 1.54" stroker cranks for the 82/92 series. It came with a new crank bearing seal and a slightly thicker cylinder gasket. It pushes the 92 to 95cc. 

Homelite Pistons. They made (3) bore sizes for the vintage saws.
-2.0"
-2 1/16" and
-2 3/16"



The 82cc engines used the 2 1/16" piston and I've found these are somewhat scarce.
Originally they were a full skirt, 2 thick rings, pressed pin, and had internal retainers, or circlips to secure the pin.
Here is a heavily modified 82cc piston. Skirt porting was a modification recommended by HL in the "How to make your Homelite kart engine Hotter" manual. 


Various other modified pistons out of HL's.


Here are the more common 2 3/16" pistons for the 92cc engines. They have thick rings, a longer pin than the 82, and the same type of retainers. The part number is usually A-57070-A. I've seen these full skirt and ported skirt from the factory.


A used, ultra-rare, single ring, factory ported KL95/100 piston. It has the 2 3/16" bore.

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I can't imagine porting the skirt somehow opens the window (pun intended) of power to these little engines. Nonetheless I plan to port them, since I didn't have a single piston that wasn't ported. (Yes, the bandwagon effect works just fine on me).
 
The piston ring locator pins are the opposite side of the cylinder from the exhaust. My understanding is if the pins face the exhaust, the engine won't last very long!



Drop the piston in and add one ring below. The skirt will have a much taller window than if you push the piston up higher with 2 rings. Homelite recommends a much more conservative approach and to stay clear of the pin bosses altogether. With that said, I have no less than 10 used pistons ported higher than the pin boss. I'm not expert on porting, or anything 2-stroke, so do this at your own risk! I'm not recommending this step.

Reeds.
This is where HL was successful with making a nice OEM piece.
 
The factory 4-petal reed cage looks just like a MC pyramid and uses steel reeds. They are easily recognizable by the staggered arrangement of the HL style washer head screws.



It will also show "TOP" because the carburetors mounted with the pulse-hole down


I have 2 Go-Power cages and a number of HLs cages to work with. I made new petals from G10 fiberglass. The advantage of the HL pyramid cage is the cage can be made flat without any special machinery. The seal is much better than the Go-Powers. You could collapse a lung trying to suck air through one of these!

(edit) Eric A. makes top shelf reeds for 4-pedal Homelites and sells them on ebay. His seller name is 310dawg

Time to secure the crank.
Be careful when selecting the 1/4 serrated split lock washers. HL used a thin one for the main bearing (pictured with the screws) and the thick ones for everything else. The thick washers won' fit into the bearing groove. The fasteners were originally unplated.



Some use blue, some use red... Some of these screws only came loose after a torch on the screw. My suspicion is the blue is fine for this application.

Put the washer in first then thread the bolt. If I hadn't mentioned it yet, all of the holes were chased at some point after disassembly.


I could be years before I run these engines. Sometimes I go months between projects. Just a few pen marks on the head indicates it's ready to use. I couldn't find a reference for a torque measurement in a manual. Keep in mind these screws are not torque to yield the way a rod bolt is. Nonetheless, tight is better than loose.


Piston and Rod assembly:

I already mentioned the 27 needles and how to handle them. After cleaning, load up the needles with petroleum jelly or something that will wash out quickly. Count and triple count the 13 + 14 needle split.


Install the rod with the "pip" (or whatever you want to call it) on the intake side. It's just that raised area just to the left of the red line.
 
Torque the NEW rod bolts to 55-65 inch pounds. The hex drive you need is 9/64". These are not the 10-32 bolts you're used to with the MC. It's 8-32 for the 55002-W rods.


Ring locators on the intake side. 

If you use a heat gun, there is no effort to pressing the pin in. Just remember the open end of the wrist pin is on the timing cover or flywheel side.


Closed end on the PTO side. Check snap rings again and make sure they are in the grooves.

Cylinders.
 
Homelite used the die-cast aluminum cylinder with the chrome plating. It's compact, thin wall, and really light weight. The disadvantages of the HL are many. The port layout is almost the same from the late 50's to the mid 60's. When the chrome chips or flakes, the cylinder is a display only. The better cylinders are really hard to find NOS.
 
The performance manual Homelite published takes an 82cc engine walks you through modifying it to 92cc. Some examples are:
-larger cylinder.
-porting the block, piston, and raising the exhaust.
-shaving the flywheel.
 
It just so happens the (2 1/16") bore cylinders are really difficult to find. The (2 3/16") are much easier to find.
With that said, these will be assembled with unmodified (2 3/16") cylinders.
 
From left to right.
casting number 56834...57645....57365

All of these are the same bore, but there were some subtle differences in the port layout. 




The 56834 prior to engine serial number 1077296 would be the "old style" ports. After that serial number the 56834 cylinder had the "new style ports. The 700 saw had this cylinder as did the early 92s.




The 57365 cylinder always had the new ports and was found on the newer 92 and 95/100. It's also found on 775D saws.



I don't know much about the 57645 cylinder except some had an area on the fins machined for some saws. Two of mine look like the new style ports and one looks like the old style.
Some of the saws which may have these are the 707D and 770D.

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EDIT. The 82cc kart engines as well as a few saw engines had the 2 1/16" bore. Some saws where you could find this rare cylinder are:
5-20
7-19
7-21
and EZ-6


The Wiz and Zips you see everywhere are 77cc and 2" bore. The exception is the Super Wiz 80 and is very collectible!