Hole in valve insert

JohnnyTillotson

JohnnyTillotson

#1
#1
Is this hole to the left of the exhaust valve part of a compression release system? This motor makes a really weird sound when you turn the crank slowly. Kind like those little novelty cans you used to turn over and it would make the sound of a cow in heat back in the 70's. So I think it's got some kind of compression release. looks like I should run a wire into the round hole to clean it out no?



This is that mess of a motor with the playboy decal on it that came with the El Tigre. Looks nice now.

 
MB165

MB165

Active Member
#2
#2
i had a discussion about that with peekster and chatten at windber last year, we thought it was someone had a hard time pulling their engine over and did it themselves. but peekster said it came off a factory origional rupp.... I think its now safe to say this is some kind of a factory?? machine shop?? compression release. look back through my posts a couple three years, and i had one of these blocks too, up until i junked it last summer........
 
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markus

markus

Well-Known Member
#3
#3
Pre '70 steel sleeve small H blocks had that instead of the extra bump in cam lobe, I have a 1969 Rupp H35 like that and also an '69 H25 that is the same. I dont know if that was a late 60's thing only or if they did that for a long time before that. They revamped in 1970 and put an extra bump in the exhaust lobe on the cams as well as dropping the steel bore liners. The fairly new to the lineup HS40's used a flywheight on the cam and they also switched to the extra bump in 70 as well, they were aluminum bore from the get go and that probably showed tec they could drop the liner in the H engines as well since the HS was holding up.
 
MB165

MB165

Active Member
#5
#5
i wonder if its a rupp factory mod, or a rupp "spec".
but you have a side popper, did rupp make a side popper equipped mini?
 
markus

markus

Well-Known Member
#8
#8
MB165 said:
i wonder if its a rupp factory mod, or a rupp "spec".
but you have a side popper, did rupp make a side popper equipped mini?
Click to expand...
:laugh: I doubt it, That was Tecumseh's "EZEE-start" for the small frame H, you can even see it in part numbers. The cam is 31317 (no compression release) on the '69 and in 1970 the part number is 33149 "compression release". Of course the block numbers changed to and the parts description will note cast iron (part number 30644a) and the '70 33077......this is comparing a 1969 Rupp scrambler engine h35-45210G and a 1970 Rupp Scambler engine H35-45304H

The 1969 side exhaust I have was not a mini bike engine, it has all the makings except the throttle assy has the bolt adjuster in lieu of the cable collet and torsion spring so it was a fixed throttle application originally (an Rupp didnt use any side exhaust engines).

I haven't run any H35's without comp release on them...yet. I did a couple of the pre 70 HS40's in the past by pulling the flyweight pins and its pretty noticable when starting, I am working on a couple of H35 right now and worked the bump off the 33149 cams (one is a 1971 H35 the other is for a custom later model 3.5 sidepopper that uses the larger HS sized crank and rod and big exhaust valve) but I am only to assembled longblock stage on the 71 and havent started paintwork or anything yet....



I left the govener gear out....OOPS :wink:



I'd be interested to see if the drilled hole was standard in the '60's I don't have any engine's earlier than the 2 1969's right now though. I only have a shroud and numbers From a 1962 H35, but the part numbers wont pull up anything online anymore and I sold off all my old parts books and manuals. You really gotta look for the hole when you pull an old engine apart, the carbon usually just camouflages it and you wont really notice it until you start cleaning.
 
JohnnyTillotson

JohnnyTillotson

#9
#9
Hey Markus, check out the pic I posted of the Bee Spraying H30 Tecumseh I posted a few months ago. Not close enought for a definitive answer but look at that square thing near the exhaust valve. That's a '68. This Playboy motor didn't have a tag so I don't know the date...

I'll have to see if I have any close ups on my phone of this one. I know I took a lot of pics as it was so pristine.
 
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MB165

MB165

Active Member
#10
#10
I had thought of brazing it up, or hammering a wire gauge drill bit shank into it. mine was drilled close to the seat area, not much room to recut....its good to know now, ezee start....huh, ill never let another go.
 
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