HS50 Camshaft help.
- Thread starter Sprocket86
- Start date
- Tags camshaft hs50
markus
last summer markus i pulled apart hs-50 snowblower engine. one of the last flatheads they made. that engine had a steel cam in it with the release valve built into the back of the cam just like the plastic cams are built on ohh-motors. i did install it in my mild built ohh-motor without the release valve. but just like the guys where saying i have to watch how i pull it over.
i have also found after the engine has warm up and then shut off and then started up again. i have found holding the kill switch helps prevent kick back when it wants to try ignite the gas thats might be left in the engine. when trying get it on the correct comp/stroke.
also notes the plastic cam's mic out the same has the newer steel cams
i have also found after the engine has warm up and then shut off and then started up again. i have found holding the kill switch helps prevent kick back when it wants to try ignite the gas thats might be left in the engine. when trying get it on the correct comp/stroke.
also notes the plastic cam's mic out the same has the newer steel cams
here is the newer style release valve out of one of my ohh -motors. this design also was uses on the last years of the flatheads.
FRONTSIDE
BACKSIDE. look real close to the lobe and you can see the little lever coming threw from the other side of the gear.
old style cam. back side of the lobe has just little bump.
two cams next each other. newer cam lobes are rounded on the ends. same goes for the newer steel cams too(sorry no picture of a newer steel cam)
older cams look to have a flatter lobe end.
also note for a 40+ year old cam, it still has the machine lines on the lobes. definitely must of been made out of some good steel.
FRONTSIDE
BACKSIDE. look real close to the lobe and you can see the little lever coming threw from the other side of the gear.
old style cam. back side of the lobe has just little bump.
two cams next each other. newer cam lobes are rounded on the ends. same goes for the newer steel cams too(sorry no picture of a newer steel cam)
older cams look to have a flatter lobe end.
also note for a 40+ year old cam, it still has the machine lines on the lobes. definitely must of been made out of some good steel.
That was problaby an LH195sp that you got that cam out of, that was the 5.5hp flathead. its still an HS for the most part, the cam is the difference though, so maybe its what gave it that extra .5hp :laugh:
I wish they (the cam) was a little cheaper to buy, I have found either the original 1968-1970 HS40 mechanical cam or modding the bump lobe cam in the HS40's to be stronger out of the hole, I didnt try the HS50 I had the cam in on anything only bench run, the HS50 will pull out of the hole pretty hard without any mods though so I dont know.
They did a mechanical for the last small frame H engines too, when they reintroduced the "H40" designation (just rated the H35 design as 4hp) they used a mechanical release cam. Those pull hard for the engine size as well. I am on the hunt for one of those for an interesting H35 build I am currently working on that uses the larger HS bottom end and still has the largest valves they offered for in the H smalls. (cam part number 32197a if anyone has one :wink
, although those aren't too hard to pull through with a modded cam in them....but I do want to shave the head a touch.
I wish they (the cam) was a little cheaper to buy, I have found either the original 1968-1970 HS40 mechanical cam or modding the bump lobe cam in the HS40's to be stronger out of the hole, I didnt try the HS50 I had the cam in on anything only bench run, the HS50 will pull out of the hole pretty hard without any mods though so I dont know.
They did a mechanical for the last small frame H engines too, when they reintroduced the "H40" designation (just rated the H35 design as 4hp) they used a mechanical release cam. Those pull hard for the engine size as well. I am on the hunt for one of those for an interesting H35 build I am currently working on that uses the larger HS bottom end and still has the largest valves they offered for in the H smalls. (cam part number 32197a if anyone has one :wink
, although those aren't too hard to pull through with a modded cam in them....but I do want to shave the head a touch.markus
YEP,
funny thing is when i look up this engine they want to sell me a plastic cam? this engine came with a steel cam.ut:
https://www.hahahahahahahahahahahah...ntal/lh195sp/lh195sp-67522d/engine-parts-list
looks like this web site is block........ i just under jacks small engines
i did find something interesting. piston and ring design is totally different from a early hs-50 engine.
if a guy was looking to find a up grade in performance. i would think the newer piston with the thinner rings and lighter piston would be a plus to have. also my ohh-motors come with thinners rings too,but i do believe my piston is little different? same bore 2.795
funny thing is when i look up this engine they want to sell me a plastic cam? this engine came with a steel cam.
ut:https://www.hahahahahahahahahahahah...ntal/lh195sp/lh195sp-67522d/engine-parts-list
looks like this web site is block........
i just under jacks small enginesi did find something interesting. piston and ring design is totally different from a early hs-50 engine.
if a guy was looking to find a up grade in performance. i would think the newer piston with the thinner rings and lighter piston would be a plus to have. also my ohh-motors come with thinners rings too,but i do believe my piston is little different? same bore 2.795
Yea, even if you look up an HS40 or 50 from the 1970's they want to sell you that plastic 37671 cam for it as a replacment for the NLA one.
Same goes for those new designed pistons with the thinner rings, you do have to watch that if your mix and matching rings for tighter clearances and things like that. because they list that updated piston number but maybe not a matching ring set for that piston # in some of the old parts listings......I found that out with an HS40 last year the hard way, ended up with a thin ringed piston and thick set of rings for the old original design :doah:
Same goes for those new designed pistons with the thinner rings, you do have to watch that if your mix and matching rings for tighter clearances and things like that. because they list that updated piston number but maybe not a matching ring set for that piston # in some of the old parts listings......I found that out with an HS40 last year the hard way, ended up with a thin ringed piston and thick set of rings for the old original design :doah:
Himm good things to know and thanks!
I wonder if finding a healthy LH195SP aka HS55 would be good to use for a mini bike application? Like transfer all of the older looking shrouds and fuel tank and paint the raw aluminum block either white or the dark grey.
What do you think Markus, could this be done?
I wonder if finding a healthy LH195SP aka HS55 would be good to use for a mini bike application? Like transfer all of the older looking shrouds and fuel tank and paint the raw aluminum block either white or the dark grey.
What do you think Markus, could this be done?
LH195SP would be a great motor to build..............BUT it comes with a step crank that needs to be change out and has a small exhaust valve that also needs replacing. if you deside to go with a heathy cam. for example a 245 dyno cam and a billet rod. you can purchase the hot coil tecumseh sold and you can still find them. bolt that on and it advances your timing. much more things you could do,but that would be a good start...:thumbsup: also everthing that i am finding is telling me the ohh-motor parts will work with the 5hp flathead. i just purchase a new 3inch crank for my ohh-motor on ebay for $40 ship to my door and it came with a threaded crank end for a clutch or torque converter setup....:thumbsup:
Yes, it can be done I use later model parts all the time. Problem with 1995 and newer is the rough casting on the blocks and the shrouding really makes it hard to hide since you have to use a later shroud to clear ignition.
For an example this is a late 1970's small frame I redid for someone last year (this is a true mini bike spec engine in original tins) This tinwork ran from mid 70's-1984 so its correct for bikes that were still around at that point:
This was a 1995 small frame that originally had the fanblade style recoil shroud, but I used a 1985-1994 recoil on, you can see that they had to widen the shroud to clear the ignition change in 1984/1985. Still kinda gives that older look at least though, and with a few other older style parts, it does not come out too bad:
Alot of parts cross as well, as you can see from things that delray was saying. major changes to flywheel style limit to you the most because of its size and the taper they used. But the later they got the more universal they became, thats why alot of the OHV parts even cross with the L heads at that point.
For an example this is a late 1970's small frame I redid for someone last year (this is a true mini bike spec engine in original tins) This tinwork ran from mid 70's-1984 so its correct for bikes that were still around at that point:
This was a 1995 small frame that originally had the fanblade style recoil shroud, but I used a 1985-1994 recoil on, you can see that they had to widen the shroud to clear the ignition change in 1984/1985. Still kinda gives that older look at least though, and with a few other older style parts, it does not come out too bad:
Alot of parts cross as well, as you can see from things that delray was saying. major changes to flywheel style limit to you the most because of its size and the taper they used. But the later they got the more universal they became, thats why alot of the OHV parts even cross with the L heads at that point.
Yes, it can be done I use later model parts all the time. Problem with 1995 and newer is the rough casting on the blocks and the shrouding really makes it hard to hide since you have to use a later shroud to clear ignition.
For an example this is a late 1970's small frame I redid for someone last year (this is a true mini bike spec engine in original tins) This tinwork ran from mid 70's-1984 so its correct for bikes that were still around at that point:
This was a 1995 small frame that originally had the fanblade style recoil shroud, but I used a 1985-1994 recoil on, you can see that they had to widen the shroud to clear the ignition change in 1984/1985. Still kinda gives that older look at least though, and with a few other older style parts, it does not come out too bad:
Alot of parts cross as well, as you can see from things that delray was saying. major changes to flywheel style limit to you the most because of its size and the taper they used. But the later they got the more universal they became, thats why alot of the OHV parts even cross with the L heads at that point.
For an example this is a late 1970's small frame I redid for someone last year (this is a true mini bike spec engine in original tins) This tinwork ran from mid 70's-1984 so its correct for bikes that were still around at that point:
This was a 1995 small frame that originally had the fanblade style recoil shroud, but I used a 1985-1994 recoil on, you can see that they had to widen the shroud to clear the ignition change in 1984/1985. Still kinda gives that older look at least though, and with a few other older style parts, it does not come out too bad:
Alot of parts cross as well, as you can see from things that delray was saying. major changes to flywheel style limit to you the most because of its size and the taper they used. But the later they got the more universal they became, thats why alot of the OHV parts even cross with the L heads at that point.
Speaking of donor engines, I'm going to check this out today.
What year range do you think this HS50 is from Markus?
Up here in Canada in the retail market we have sold probably millions of snowblowers over the decades so there are a lot of potential engines for mini bike and Kart use. Trouble is that the all the snowblower manufactures never really settled on a standard PTO spec. The sizes are all over the map.
If you go back and read my last post it shows the year info for the shroud configurations, compare it to the one you have there :smile:
Yes they did make a factory block off plate, usually the 120v starter was an optional accessory. You can probably find a part number for it with the numbers you will find stamped on top of the shroud since it is a snowblower spec engine.
Yes they did make a factory block off plate, usually the 120v starter was an optional accessory. You can probably find a part number for it with the numbers you will find stamped on top of the shroud since it is a snowblower spec engine.