How to ID this H30?

NorCal

Active Member
#1
Looked everywhere and I could not find a VIN or serial number anywhere. How can I ID this thing so I order the correct parts for restoration?
 

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#2
No tags? I'm pretty sure only sears used that style head with curved fins.
My favorite side popper. Would make a really cool looking engine with the carb swapped to the exh port.
 

NorCal

Active Member
#3
No tags? I'm pretty sure only sears used that style head with curved fins.
My favorite side popper. Would make a really cool looking engine with the carb swapped to the exh port.
Negative, no tags.

This is the crack up (to me). This engine and frame have never been together, and were painted on opposite sides of the county. Engine from New York, frame from San Francisco. Hell the colors are identical. I painted the frame with a 1960's Pontiac valve cover paint.

I've had this thing and a few parts for a decade sitting in my shed. I'm just getting around to piecing this thing together. Engine runs good, carb is leaking though.
 

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delray

Well-Known Member
#4
you might want to think about using that jackshaft setup. that engine is only going to be around 3hp and from the looks of that front tire(tall) thats not going to help that little engine move out either....:scooter:
 

NorCal

Active Member
#5
you might want to think about using that jackshaft setup. that engine is only going to be around 3hp and from the looks of that front tire(tall) thats not going to help that little engine move out either....:scooter:
What are the advantages of using a jackshaft? I'm new to mini bikes.
 
#6
What are the advantages of using a jackshaft? I'm new to mini bikes.
A jackshaft can allow a higher overall ratio (commonly referred to as lower gearing) than is possible with a single reduction (clutch to wheel). You are limited by ground clearance as to how large the rear sprocket can be. A jackshaft provides a double reduction, the first reduction is multiplied by the second to determine the overall ratio. The math is simple but, if you dislike doing math, BMI has a handy jackshaft calculator.

https://www.bmikarts.com/Go-Kart-Gear-Ratio-Calculator-Jackshaft-Setup
 

delray

Well-Known Member
#7
it should help the bike take off better out of the hole and your weight can be a big factor also on how it will pull you down the street and on the clutch. sometimes the clutch can really struggle on a low hp engine more then just one way. I'm surprised you really don't have any clue on a jackshaft advantages. been a member for over 5 years here....lol. maybe start a thread project build if you decide to make a build out of it.... thumb1.PNG
 

mustangfrank

Well-Known Member
#8
Looked everywhere and I could not find a VIN or serial number anywhere. How can I ID this thing so I order the correct parts for restoration?
I can't quite tell from your pictures but if there are two rivet holes on the side of the shroud (where a large metal ID tag was) that would date it to circa 1972 or earlier.

You'll have to search images of other engines, matching the diaphragm carb, air cleaner, tank style, etc & use the model number off a match to lookup parts. Probably just type in H35- over at Jack's Small Engines or wherever, a bunch of different models will be in the drop down menu. A few tries and you'll find one with a diaphragm carb for a rebuild kit part number.
 
#9
I was under the impression that only Tecumseh in Italy used curved fins on the cylinder head. If the engine has metric threads it was made at the Italy plant or the curved fins could be a variation requested by Sears for their products. This is my guess, @markus would probably know for sure about anything Tecumseh, that's his specialty.
 

markus

Well-Known Member
#10
Looks to be a mis-mash of parts as it sits, you would want to check bore and stroke measurements before assuming its HP/cc rating etc.. there will be numbers stamped on the carb itself (on the mounting flange) you can use those to cross refence the carb #'s so you get the correct parts. While those heads look neat, here in the US they were "Low compression" heads with a larger chamber in them, (cant tell from the photo's if its one or not). The shroud is around 1966-1969, the recoil is earlier, and bolted on where it should have been riveted on that version shroud, etc... Also look for a little folded over tag that is bolted to the valve cover or possibly a sidecover bolt. They made engines for some other companies as well and they used a little tag instead of the typical business card sized one riveted to the shroud even though the holes would still be there to mount that style tag might get lucky and find that to cross reference.
 
#11
Only curved fins I ever saw were on eager-1 craftsman engines. My dad had a 3 hp edger with one, and the primer bulb. Some of the rotary mowers had them too. Neat looking, but had no idea they are low compression.
 

NorCal

Active Member
#12
I'm surprised you really don't have any clue on a jackshaft advantages. been a member for over 5 years here....lol.
Well I could baffle you with B.S. or I could admit what I don't know. I choose the later. Not everyone is an expert, some of us have to start somewhere. Lucky for me, I choose to be here on the forums were there are some experts that know way more than I do, and are gracious enough to answer my stupid questions. . .
 

NorCal

Active Member
#13
Looks to be a mis-mash of parts as it sits, you would want to check bore and stroke measurements before assuming its HP/cc rating etc.. there will be numbers stamped on the carb itself (on the mounting flange) you can use those to cross refence the carb #'s so you get the correct parts. While those heads look neat, here in the US they were "Low compression" heads with a larger chamber in them, (cant tell from the photo's if its one or not). The shroud is around 1966-1969, the recoil is earlier, and bolted on where it should have been riveted on that version shroud, etc... Also look for a little folded over tag that is bolted to the valve cover or possibly a sidecover bolt. They made engines for some other companies as well and they used a little tag instead of the typical business card sized one riveted to the shroud even though the holes would still be there to mount that style tag might get lucky and find that to cross reference.
I will snap some more pictures of it sometime this week as I need all the help I can get. The carb set up (at the least the rebuild kits I see online) look to have different seals that this one has. Might be a hodge-podge of parts slapped together, but outside of the carb leaking, it runs like a top. The guy I got it from said it was a 3hp which is where I got that from. As far as meassuring the cylinders, I have no idea how to accomplish that and I dought I have the tools necessary? I'm sure the cool kids have more than I do with a basic tape measure, lol.
 

NorCal

Active Member
#15
here's a sears motor I have with the tag if it might help??
I'm no expert, but that looks identical to mine (minus the missing decals and tags). That square thing on the underside of the carb is where it leaking from. I also changed out the fuel line as the other one was as hard a chinese algabra.
 

delray

Well-Known Member
#17
I'm no expert, but that looks identical to mine (minus the missing decals and tags). That square thing on the underside of the carb is where it leaking from. I also changed out the fuel line as the other one was as hard a chinese algabra.
when you take that style carb apart it is very important install the diaphragm/gasket in the correct way and needle...etc.. maybe someone will chim in on a good photo how the parts are installed correct on that type of carb.
 

markus

Well-Known Member
#18
I will snap some more pictures of it sometime this week as I need all the help I can get. The carb set up (at the least the rebuild kits I see online) look to have different seals that this one has. Might be a hodge-podge of parts slapped together, but outside of the carb leaking, it runs like a top. The guy I got it from said it was a 3hp which is where I got that from. As far as meassuring the cylinders, I have no idea how to accomplish that and I dought I have the tools necessary? I'm sure the cool kids have more than I do with a basic tape measure, lol.
post #10 in this thread: 1970 h35 rupp sprint specific I focused on rebuilding the diaphragm carbs that were specific to the recreational/mini bike engines for slanted application pre 1971. your primer bulb/industrial will vary a little in setup but is internally a similar fashion. You can see where the numbers are stamped on the flange (what I referred to in my previous post) that you can cross reference from a thread/link located here in the Tecumseh forum in one of the top "sticky" threads called Tecumseh carb number stamping guide that was supplied by outdoorpowerinfo.com

Once you get that # you can use that to pull up the parts lists specific to that carb, which usually also show a generic explosion of the carb to help better understand which way things go, as well as all the part numbers specific to that particular carb. Good rebuild kits usually also have the info for placement of the diaphragm gasket depending on carb body design. Rebuild kits for these usually cover many different models, so they come with spare parts depending on application as there were many variations based of the diaphragm carbs so that can be confusing if looking at a kit, Its just important that you use the correct kit, or if buying ala carte to get the correct specific pieces that your carb body used.
 

NorCal

Active Member
#19
See below. That 19-0-54 is the only stanping I can find on it. Below the carb I can make out another set of numbers, but I'd have to strip the paint in order to read them.

IMG_0486.JPG IMG_0487.JPG IMG_0488.JPG IMG_0489.JPG IMG_0490.JPG IMG_0491.JPG
 
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