Guys,

I have an older G-38 with the original carb w/no choke. I want one w/ a choke, and I've read the WT-540 is a great replacement, and Horizon shows the WT-338 as the o.e. replacement.

Does anyone know if either or both carbs will fit the spacer block on my old engine, with the same odd-ball linkage as the original? Do you have a good source for your carbs?

Thanks,
Rick

I recently bought a wt 540 for my G38. Dont know if my engine is the older version because I bought it as a short block - but I am guessing that it is since it was from an estate sale.
The carb fit perfectly on the spacer. As far as I know all WT carbs have the same bolt pattern. I also managed to turn the spacer around to provide a straight linkage for the throttle - this can be done with minimum effort!

I bought mine on ebay - under lawn equipment >chainsaws, from a seller going by 'michaelr'. Still havent had time to run it yet though.
Hope this helps.

Go to ebay and look up:
[ecedwards_tools].i buy all my carbs from him-$9.00to-$14.00 uasually.brand new.never had one fail me yet.

I changed mine to the WT 338-1 with choke and I used the EasyLink carb adapter from Horizon. It works fine. I bought the carb from VE Petersen Co, do a Google.

Thanks, guys. Ebay it is!

Buck, do you have a phone number for ecedwards_tools? I want to call him and buy direct.

Thanks,
Rick

Hi Rick,
You may want check on inter-changability.
If your G38 has the skinny iron prop hub, i don't think the carbs can be switched because the small holes may not line-up between the newer WT 338 and the old style G38 carb flange. It will bolt on, but the small holes may not line-up. The newer style G38 has the larger aluminum prop hub with the WT 338 carb.

Thanks, Hogrider. Does anyone know exactly how I would find out which carb fits my engine?

Thanks,
Rick

Check with Ralph at [email protected]

or at rcignitions.com

No i dont have his phone number as i buy and sell on ebay and hes saved in my sellers folder.I do it this way as we both recieve feedback from our transactions.I would do as suggested by calling ralph.Whatever number he gives you try ecedwards.I have an assortment of carbs here that i could matych up and if not i could order from ecedwards but it would take a while us doing all this swapping.Ill go look at what horizon says.

I checked horizon and the 338 has a 13.49 venturi after checking walbros specs.The pic of the 338 on horizon shows the pulse hole centered.I have 2 carbs here that are 13.49 venturi,#34 in intake.One of mine has the automatic choke,this when flipped on,stays on until the throttle is moved.Operated by a spring.Its number is WT542,has a nice throttle arm for easy hookup.
The other one has 2 nice long shafts sticking out of carb for a easy fit of the steering arm or throttle arm from the easy carb kit from Horizon.This has the standard choke setup.Its number is WT414.Both of these i bought from ecedwards.
Niether one of these has the primer bulb.To me i think these are a little large because these are what i run on my 45-52cc engines.Anyway,these match the venturi that horizon says.Both of mine have the pulse hole centered.

Hi,
Before I would swap or buy anything, I would check with the expert (Ralph). That way you can make a educated decision.
He also makes a Carb Adapter (a little thinner than stock) to bring inline the throttle lever with the Throttle Servo Rod, for a straight push-pull action.
You might want to check-out his Battery Ignition System. Much lighter and easy starting than the stock G38 Mag System.

Ralph Cunningham - Owner
1800 Whitehall Dr.
PO Box 636
Williams, AZ
USA
86046

928-635-2455

Buck and Hog, thanks for all your info.

Rick

Rick,
Here are a couple of pics of my G 38 in the process of being converted to ei. The carb block is rotated and a new pulse hole drilled. the old one can either be covered by the two gaskets on either side or filled with some epoxy. I also mix the epoxy with chopped fiberglass strands to fill any counter sunk holes etc I dont need and to make it look more "professional". I have been doing this on all my 'conversion' engines and its worked out great so far- no air leaks etc..

Thank you, King. Is that the WT-540 carb? Your job looks good to me.

I'm not sure when my G-38 was manufactured, but I did find that it has the aluminum prop shaft, and the WTA6A carb w/no choke.

I found a useful article, both in terms of carb replacement and ignition conversion. Looks like the WT-540 is a bolt-on fit:

http://tech.flygsw.org/g38ignition.htm

The WT-540 is the way I wanna go, as I like the auto choke shutoff and large bore.

Look at my pics,i have the WT542 as i posted ealier.Looks like the same as the 540 but with just shorter needles.
Go to ecedwards_tools.I just looked.Click on carbs.
WT540$14.99
Wt542[like mine]-$12.99mine has the auto choke also as you can see in the pic.

Thanks, Buck. I sent you a pm.

Hey Rick,
yup, thats the WT 540 carb with a 13.49 mm venturi. The new zenoah's come with the wt 338 (which is also a 13.49 mm, as was mentioned earlier in the thread by Buck) and the aluminum prop hub, so yours seems to be a weird hybrid if you bought it retail! Otherwise someone might have upgraded it with the new prop hub. Thanks for the article - I read it some time ago and it gave me some fresh ideas. I guess I have been spending way too much time online looking at anything gas engine related. I was also trying to decide as in the article, whether to put the pick up sensor in the back or up front - both are viable options and my prop hub already has a magnet in it - its just a little far in front on the crankshaft and I was concerned, with the vibration of the sensor bracket extending that far. I guess Ill have try it out one way or the other.

by the way what plane is your G-38 going into - mine will eventually end up on a 72" giles 202

If ya wanted to you could add a spacer say 3/8ths thick to the back of your hub.Youd drill 2 holes 180degrees apart equal distance away from center to hold it on.You could make it,or have somone with a lathe make it any size you want.Then you could use the 2 front bolts on the lower case to hold the bracket.If ya really wanted high tech,the 2 bolts that hold the spacer on you could mill a slight 1/4 moon,slot so even after the hub is tightened you could adjust the timing by losening up the 2 bolts and turning the spacer a little.The spacer would hold the magnet.

thanks for the suggestions Buck. Dont want to take over rick's thread with my stuff so Ill keep it short.
I was thinking of the same thing and I already have a spacer. I really like the crescent shape idea for making it adjustable - the lack of adjustability was my main reason for holding back with the spacer on the front end. Dont really have the tools to mill the slots, all I have is dremel but I think it can be done even with the dremel with enough patience and care.
The easier option is to put it on the back - the spacer fits perfectly on the shaft and all I need is a nut to hold it down - but the gap on the front end between the hub and the engine doesnt really look that great - I guess I am stuck in the old form vs function dilemma.

I think its ok,rick bought a carb like mine anyway.The spacer should fit the front crank also because there the same size.Put it in front and ya wont need a cup mount and you can also have a shorter distance from firewall to prop.[less weight also].Tighten hub on,drill and tap holes [2] for 8-32 on hub.12 and 6 oclock.Make identical marks on spacer.Use a fine magic marker and draw an arc equal to the crankshaft 1/8th - 3/16ths each side of the marks.Start with a 1/8th drill bit and drill holes right next to one another on arc.Then step up drill bits one at a time until you get to 8-32.Then use the ball reamer,metal,not stone in the dremel and clean up.Put center of arc with center of bolts.Put magnet in 6 oclock position.Use bottom 2 crankcase bolts to hold sensor and bracket.Should take about 5 to 10 minutes per arc.This is what ive done.Use a drill press.Your going to do just as much work putting it in the rear.Plus you"ll get rid of that big space in front.

Have you run the engine with the WT-542 yet? I was going to order the 540 but didn't much like the long needles.

CR

Flatspin, I'm sorry for not responding to your question earlier. For some reason, I just got notified there were posts made to this thread.

Anywho, I installed the G-38 in a Hangar 9 P-47, and it pulls that sucker straight up! Love those Zenoah's............