Ohlsson & Rice: Drillgine Gearbox Oil or Grease

[CNew 404]

I’ve started digging into a Drillgine and I’m about to open up the gearbox. I noticed there are two threaded screw plugs that look to be oil fill holes, one on each side of the gearbox. Is this gearbox intended to be filled with oil or a light grease like Lubriplate. If it’s oil, what weight/type and how much?  

 

Also, if anyone has any tips on things to watch out for or common surprises when opening these gearboxes please let me know.

 

is there a good substitute for the large rubber seal/ring that is on the outside output side of the engine between the engine and the gearbox?

 

Thanks,

Clint

[factory 487]

The Bridges drill gearbox uses oil, with top-ups every ten hours of use, I imagine the Drillgine will too.

 

The seal, could be replaced by a O-Ring of the correct diameter & thickness if you can't find something similar to the original & if it's not reusable.

 

Pictures below of the Comet drill manual (which is the same but without the throttle control) from 'Neons' sale thread;
 

 

 

David

[CNew 404]

Awesome, thank you David!

[CNew 404]

Any tips on how to remove the chuck? The service manual suggests using the chuck key but that didn’t seem to work. 

 

Also, I opened the oil fill plugs and it was 100% dry as a bone in there, not a single drop of oil and the gear teeth aren’t even oily or greasy.  No signs of dried grease either. Does anyone know if the gearbox is a sealed two-piece construction where one half would have some lithium grease on the gears and the other side has oil? Or, does the oil flow all throughout the entire gearbox? I’m guessing if the oil goes all over then it’s a wet clutch?

[factory 487]

Exactly as the instructions say, insert chuck key into a hole in the chuck (green arrow) and using a hammer strike so that it will go in a anti-clockwise direction (blue arrow). The same technique could be used on old electric drills, to replace or upgrade the chuck, or in the case of some drills allow the use of certain attachments.

 

 

Maybe all the old oil has leaked out, the two halves are not sealed as the reduction gear passes through the middle section.

 

David

[CNew 404]

Thanks David! That’s the technique I tried without any success.  I’ll give it a couple more attempts. I didn’t want to go at too hard as I just k ow if I would mess anything up. I appreciate you confirming the process. Also good to know the two halves aren’t sealed. As always all your technical expertise is greatly appreciated!

 

Clint

[Wallfish 698]

Take out the screw inside at the bottom of the jaws first, Tighten a 1/4" or bigger hex tool into the jaws and strike that rather than using the key in the hole. There's too much risk of damaging the the teeth on the chuck by using the key in one of the holes if it doesn't come loose very easily. You can also use a straight 1/4" hex tightened in the jaws and use an impact gun on the other end to get it loose.

 

Don't see a screw in the drawing above but that's how most chucks are fastened. Skip if not present

[factory 487]

21 minutes ago, Wallfish said:

There's too muck risk of damaging the the teeth on the chuck by using the key in one of the holes.

 

Possibly not the original key then (mine is missing too), you would use the handle end of the chuck key in the hole (key below). Can you confirm there is a screw down the centre of the chuck, it's a bit late for me to go & check tonight. Usually reversible drills have the screw down there.

 

 

This must be the other technique John is referring to, I don't think the chuck in this video has been in very long, it came off far too easily.

 

https://youtu.be/N4ycjguUFZk

 

David

[Wallfish 698]

Wollowing out that hole for the key is another issue with doing the way the instructions state. Use the chuck jaws clamped down on a hex to be safe.

[CNew 404]

Great suggestions.  I just verified there is no screw in the center base of the jaws.  I attempted the idea of chucking a hex and then hitting that and unfortunately that didn’t work either. This thing is being quite stubborn. Feels like if I hit it any harder I could jam something up in the gear box or in the engine.  I may have to try the impact wrench idea next.

 

Just to clarify, when it states to hit it in the counter clockwise direction I’m understanding that to mean CCW looking straight at the chuck, as David showed in his arrow picture, and not looking at it from the rear of the drill? CCW looking straight at the chuck would be the “Forward” direction for drilling.

[Wallfish 698]

They don't come off easy! Especially one that's been on there since the late 60s. The sudden impact it was cracks it loose as it's on there tight. Try the impact gun.

CCW looking straight at the chuck jaws.

[CNew 404]

Thanks for the tips John, I’ll give that a try.

 

Clint

[CNew 404]

John,

  I had a chance to try the impact wrench this evening and that did the trick!

 

Clint

[WOWaLotOfBees 0]

I always use a long and fat hex key to remove chucks. For my drillgine it took quite a few tries. Striking the very end of the hex key tightened into the chuck with a sharp and quick tap with a rubber mallet has been a sure-fire method for me. I have never tried to use an impact driver, I will have to try that next time I am having trouble with a chuck.

[CNew 404]

Hopefully next time I won’t need to go to this extreme. I’m not sure why it was being so stubborn. It wasn’t rusted or anything either. I have a hex socket that chucked nicely and then I used the impact wrench, worked pretty well actually.

[factory 487]

Good to hear the impact driver sorted it.

 

7 hours ago, CNew said:

I’m not sure why it was being so stubborn.

 

Probably because it's been on there a very long time, plus in normal use the chuck will self-tighten the same as the chucks for my small lathe do.

 

Now that ePay have sorted out completed listings (was showing no items for about a week for me) I see there were some NOS gearbox seals sold recently, so they are out there, though they could be just as perished as the original.

Also I can't remember if we mentioned this before, but if the engine PTO shaft seal is bad it will suck all the oil out of the gearbox, again a suitable sized O-ring can be used to replace this if necessary.

 

My Drillgine has the rebranded AEP engine, which is the newest engine in my collection, dating from August 1978.

 

David

[CNew 404]

I’ll look into the o-ring solution. I did find one seal on eBay so I can use it to figure out sizing.

[CNew 404]

Thanks again for all the great advice and tips.  We will see how things look once I open the gearbox and go through the engine.

[Wallfish 698]

@Webhead Joe posted a technique using a blown up balloon attached to the exhaust manifold to check and test crank seal leakage. A 2 stroke engine needs the case sealed to perform properly, not saying it won't start and run with leaking seals as I have many that do. But, any engine that gets pulled apart, you might as well do the seals. Much easier for me as I have a stash of parts but just thought I'd throw this out there.

 Easier starting and you can adjust the carb without the engine "wondering" between good performance and bad at different RPM. More critical on anything with a throttle control because of the idling to full rpm. .

I might have some gearbox gaskets too but... If you're going to get into taking these things completely apart then do yourself a favor and get a diversified stash of gasket materials, a good set of sharp scissors and some hole punches. Make your own gaskets which will save a lot of time and the initial expense will pay for itself fairly quick.

[CNew 404]

John,

   Great advice. I think I have the gasket materials covered but seals are a bit more challenging, except for the once where an o-ring will work. After looking at the drill a bit more I may not take the engine completely apart. The gear boxes aren’t an issue. I’m still trying to build up a stash of parts and unfortunately shaft seals don’t seem to come up very often so I’ll probably need to be fairly selective and cautious on which engines I end up going through completely.

 

Speaking of idling, for a standard engine with no throttle control do these engines typically race at full rpm?  I started one up the other day and it didn’t seem to want to idle, rather it seemed to rev at very very high rpm.  I’m still learning about 2 strokes and how to tune them.

 

clint 

[factory 487]

18 hours ago, Wallfish said:

Joe posted a technique using a blown up balloon attached to the exhaust manifold to check and test crank seal leakage.

 

It can be found in the Engine rebuild sticky thread;

 

18 hours ago, CNew said:

Speaking of idling, for a standard engine with no throttle control do these engines typically race at full rpm?  I started one up the other day and it didn’t seem to want to idle,

 

Is this the engine that had the missing carb spring & retainer for the throttle spring?

Things to check, the throttle butterfly moves freely & springs back OK, also check the governor vane hasn't popped out of it's locating hole & it's not bent out of shape (if it has the metal vane type on the flywheel end).

 

David

[CNew 404]

Thanks David!  This engine has all the Governor and carb pieces.  I’ll check again to see about the Governor vane but I think it was attached.

[Wallfish 698]

23 hours ago, CNew said:

Speaking of idling, for a standard engine with no throttle control do these engines typically race at full rpm?  I started one up the other day and it didn’t seem to want to idle, rather it seemed to rev at very very high rpm.  I’m still learning about 2 strokes and how to tune them.

 The screw stop is the adjustment for running speed along with the governor adjustment if so equipped.

2 Strokes run at higher rpm and O&R compacts high end is typically 6000 rpm (I believe but maybe David can verify this?)

The rpm can be adjusted by that governor adjustment thingy you needed a spring for and the screw to push open the throttle.

 not sure of your experience with 2 strokes but they do run fast and loud! Which is part of the reason why I like'm!

Post a video if you can

 

[CNew 404]

Thanks John!

I’ll see if I can get a video this weekend. I have now adjusted the Governor spring mechanism to the lowest setting and I also turned in the main adjusting screw some so I’ll see if that will even things out a bit. I’ve seen a couple videos of Orline chainsaws where they seem to have a nice low idle and triggers throttle response (like the Ford O&R chainsaw video on YouTube). I guess that’s kind of what I was thinking/aiming to achieve.

 

Clint

[factory 487]

19 hours ago, Wallfish said:

2 Strokes run at higher rpm and O&R compacts high end is typically 6000 rpm (I believe but maybe David can verify this?)

 

They were specified for 6300rpm at the full HP rating, of course it may go higher if there is a governor problem, the vane is damaged/bent or someone removes the vane assembly (common with RC modified engines).

 

Here is a typical graph showing the brake-horsepower against engine speed (for the AEP Series 13B 1HP engine).

 

I would be watching the governor vane next time you try the engine, to see that it operates & closes the throttle butterfly as the engine speeds up, if it doesn't it will run at max speed (looking for earplugs emote), if the vane falls out the same thing happens (guess how I know that).

 

The idle speed should go below the speed that the clutch (if fitted) operates at, which is a nominal 3000rpm, otherwise the clutch would never disengage.

The idle adjustment screw (top one) is there to allow the idle speed to be controlled, the more it is screwed in the more it prevents the butterfly inside from fully closing & increases the idle speed.
 

9 hours ago, CNew said:

I’ve seen a couple videos of Orline chainsaws where they seem to have a nice low idle and triggers throttle response

 

The chainsaws can't really be compared to your engine as they have the throttle control fitted (the two lower holes, below idle adjust), there is nothing stopping you from adding a control here if you want (it was an option extra for these engines), the max speed should reduce the more it's push in (I've seen screws fitted here by previous owners too).

 

David