Ohlsson & Rice: The Groomer Landscaper 600 Carburetor?

[CNew 403]

Hello All,

     I’m about to dig into this O&R The Groomer and wanted to see if anyone knows how the fuel lines should be hooked up.  There is an interesting little inlet nipple machined into the side of the engine where the mounting screws are located. Best I can tell this looks like an attachment point for a fuel line or vent hose of some sort.  The little Tillotson carburetor has 2 fuel line elbows. I’m assuming one attaches to the fuel line coming from the tank but where would the other one attach to or is it supposed to attach to the little nipple on the side of the engine?

 

Any suggestions are very appreciated.

 

Thanks!

[Webhead 95]

That is exactly where it should be connected.

[CNew 403]

Thanks Webhead!  Hope you had a great Christmas. By the way, this is the unit that generated my interest in the Tillotson HU38A carbs.

[factory 483]

On 12/25/2018 at 9:03 PM, CNew said:

I’m about to dig into this O&R The Groomer and wanted to see if anyone knows how the fuel lines should be hooked up.  There is an interesting little inlet nipple machined into the side of the engine where the mounting screws are located. Best I can tell this looks like an attachment point for a fuel line or vent hose of some sort.  The little Tillotson carburetor has 2 fuel line elbows. I’m assuming one attaches to the fuel line coming from the tank but where would the other one attach to or is it supposed to attach to the little nipple on the side of the engine?

The pipe on the crankcase to the carb is for operating the pump diaphragm with pulses from the engine crankcase.

 

Please don't use it as a parts engine as you said in another thread, it was one of three engines that originally came the seller in the linked thread below;

Here is the original ebay description (with the history) for them;

 

 

It may be the only one left, as they all ended up with the seller you got that one from, one of which got an incorrect starter fitted by that seller & the correct one sold as bits, not with the engine  (See below);

 

 

They were made towards the end of AEP, around 1977/78 so it's likely not many where sold and that makes it much harder to find a survivor.

 

 

David

[CNew 403]

Hello David!

    I hope you had a great Christmas. You’re an absolute genious on these engines.  I really appreciate the insight and knowing the rarity of this one I will not use it as a parts engine.  I would like to get it running and make it a stand-alone working display engine.  For grins and giggles I just ordered a repair kit for the Tillotson.  However, I’m hoping to work something out with Webhead on getting another HU38A carb that is in better operating condition. 

You mention an incorrect starter being fitted, can you provide some additional clarity on this detail?  Is the engine I have missing some critical starter parts needed to get it running?  Best I can tell the engine seems to have decent compression and spark so I’m hopeful.

 

I did notice that the little pole where the kill switch, condenser and points usually attach does look to be missing something. There is an open blade/tab that looks like a standard female wire connector. I’m guessing this use to be connected to an on/off switch or something but that’s just a guess.

 

Clint

[factory 483]

1 hour ago, CNew said:

You mention an incorrect starter being fitted, can you provide some additional clarity on this detail?

 

I have edited the previous post, as I was referring to the pictures with the older style starter (in yellow), the 13B should be a square type as yours has, the seller changed it for some reason.

Note the 13B flywheel is different to that of the earlier engines, it has different starter dogs for the square style starter mechanism.

 

The other thing you mentioned, the blade/tab will go to a remote kill switch on the handle of the weed wacker/trimmer.

 

David

 

[CNew 403]

Here are a couple photos during the rebuild of the Tillotson HU38A carburetor. I’m  anxious to give this engine a try soon.

[Webhead 95]

Do you have a photo of the carb to manifold gasket?

[CNew 403]

The old gasket isn’t in great shape so I was going to attempt making one and using the old one as a template, unless of course you have 

[Webhead 95]

What about the gasket between the carb and the manifold? I'm looking!

David, do you think that these would work without the pulse hook up? Just trying to see if these would make a good replacement for the crappy originals...

[CNew 403]

Fortunately the Tillotson rebuild kit came with a new carb to manifold gasket.

[factory 483]

He's got the gasket for between the carb & the engine in the kit;

 

 

Not sure there is a need to make a new gasket for the other side, as the flange fitting doesn't look to have any means to filter the air (unless he plans to make something for that too), these trimmers used a flexible pipe to extend the air filter away from the worst of the dust likely to generated in use.

 

3 hours ago, Webhead said:

David, do you think that these would work without the pulse hook up? Just trying to see if these would make a good replacement for the crappy originals...

 

It looks like the pulse tube is needed to operate the pump in the carb (shown in the top part of the diagram below), I plan to add a tube to mine for this, that the least of the problems, I can't remember if I mentioned it before but an adaptor plate is needed between the carb and the induction housing, I suspect this hasn't been pictured as it's still attached to the engine.

I did start making a diagram to produce this part, unfortunately life got in the way & I've lost the diagram too.

 

 

David

[CNew 403]

I’m in the process of trying to find a suitable clamp-on filter to fit the flange. I’m wondering if maybe even one of the larger RC car engines might have something.  I hadn’t thought about the hose idea which would make it closer to the original setup.  I’ll have to noodle on that a little more and see what I can find.

[factory 483]

20 minutes ago, CNew said:

Fortunately the Tillotson rebuild kit came with a new carb to manifold gasket. 

 

Seems my previous post crossed with yours.

 

9 minutes ago, CNew said:

I’m in the process of trying to find a suitable clamp-on filter to fit the flange.

 

That sounds good, there will be something out there as I've seen after-market filters fitted before, people with access to a lathe have made their own too.

 

David

[factory 483]

Correct me if I'm wrong, but the flange for the carb looks to be cast as part of the induction housing on this engine, which may explain why Webhead didn't have any adaptor plates when I bought one of the Tillotson carbs from him.

 

 

David

[CNew 403]

Yes, I believe you’re correct. The flange looks to be part of the casting.  When I was first taking this apart I was expecting the flange to be an adaptor plate that was fastened to the induction housing mating surface but was quickly surprised only to find that it is all one piece.

[CNew 403]

deleted to avoid confusion

 

 

Edited December 31, 2018 by CNew
Wrong diagram

[CNew 403]

I’ve been researching some 1/5 scale RC air filters and I’m hopeful I may be able to find something nice to add to The Groomer.  These larger RC trucks and Baja buggies use 23cc 2-stroke engines and the carburetors look very similar in size to the Tillotson HU38A. It still might require an adaptor plate or something so I’ll have to continue investigating.  I’ll keep you all posted if I find something.

 

Clint

[factory 483]

18 hours ago, CNew said:

Here’s another diagram for reference. This is a different “HU” Model but still helpful.

 

That one shows all the parts that aren't used on the O&R version, probably because the adjustment screws & throttle parts would fit in the space available on the 13B engine, so they had to choose the fixed speed version.

 

Note the diagram I posted is the correct version for your carb, I didn't post the rest of the page as it's from a book that is still available and I don't want any copyright problems, it doesn't say what speed it's fixed at though.

Make sure you have it firmly attached to something before starting it.

 

David

[CNew 403]

I made a gasket for the carb. Does the fuel line connection from the carb to the engine look correct?

 

thanks!

[factory 483]

On 1/5/2019 at 2:24 AM, CNew said:

Does the fuel line connection from the carb to the engine look correct? 

 

Yes it looks right to me, the crankcase pulse tube goes the pipe on the carb pump cover and the fuel line to the pipe on the carb main body.

 

David

[CNew 403]

Thanks David, greatly appreciate you checking my work! Now I just need to mount this engine securely and get some fuel to it.

[factory 483]

Maybe you need to build an engine test stand, here are some pictures of the one 'usedtoolman' built on the old forum, original post here;

https://web.archive.org/web/20130814204047/http://ohlssonandrice.forumer.com:80/engine-test-stand-t1232248.html

 

 

Here some pictures of mine, which didn't quite go as planned (I have the posts spaced a little too close together), need to drill & tap some more holes in it at some point, the large chuck of steel came from an engineering surplus stall at one of the local engine shows.

 

David

[CNew 403]

David,

     That’s great, I actually have something similar in progress.  I ordered some materials over the holidays and they just arrived. The pictures you provided do give me some additional good ideas on how to construct it.  Thanks, this is really helpful!

 

Clint