Help! Pilot Screw and threads FUBAR

Hey Fellow XJ'ers. I'm finding myself distress upon reaching the end of the "Old School" Carb cleaning method. I've gotten the carbs completely torn down per the article... all except the extraction of the pilot screw on carb #4. For starters, there were no plugs, and while screws 1-3 came ou super easy, number 4's slot was all buggered up, and the threads above it, that it screws into are also in rough shape. haven't tried drilling the screw and using easy-out yets, but I'm concerned because of the messed up threads.

Do I have *ANY* hope here? If so, where on earth will I be able to find a replacement pilot screw?

This is giving me heart burn... so any advice will be greatly appreciated (I'm prepared for the worst).

By the way, my bike is a 1982 XJ750J Maxim. When puling these puppies apart, I found that the main jets were #120, while the yamaha manual suggests that these should be #110. Oh so much confusion.

 

Blu---the main jets for 750's should be the #120 size. The 650's used the #110's.

I have replacement used pilot mixture screws available, as well as used carb bodies in case you mess up the threads on it! PM me when you finally determine what you need.

 

hey chacal, thanks for the info, both in this post, and my other. It's reassuring. I should know what i need soon, as son as I take another pass at getting that pilot screw out.

Best case, I'll need a pilot screw, worst, I'll need a carb body and pilot screw. I've seen a couple complete sets on ebay that I'm watching just in case, but if you can quote me a price over a PM, I may be able to put those thoughts to rest. Again... thanks a ton for the re-assurance!

 

Hey blue....you might be needing carb body #4, correct? That's the far right side carb, on the brake lever side of the bike.........

 

yup, that's the one. #4

 

Ahhh.. sweet success! My buddy just got home, and helped with the jam I was in. We used 1/16 drill bit to make a new slot in the screw, and then were able to back it out, ever so carefully. It looks like the threads in the actual card body might be fine... I was paniced earlier...

So, now that my carbs are bathing in carb dip, all I need now is a new pilot screw!!! I'll shoot you a PM, Chacal.

Thanks again, for the advice and moral support.

 

Wrap the Carbs in a towel and bring everything out to my place in Billerica.

We'll put them on-the-bench and go through the whole rack.
Clean
Bore Polishing
The whole nine yards.

There's a AutoZone around the corner.
(If we need Carb Cleaner)

((Bring the Bike and we'll put them on and tune them, too!))

 

Now there is an offer you shouldn't refuse! Wish I lived closer Rick. Of course you might rather live out this way...

 

Not this time of year. Oh, sure ... when the snow's flying I'd rather be somewhere where its warm. But, when the weather turns to where the Grubbs are devouring your lawn ... there's no place like being here in the Cradle of Liberty.

Truth be told, we are looking into a Southern locale for a relocation away from the ice and snow. But, that's down the road some.

In the mean time, Billerica is growing like mad and I have a few regulars who don't like getting their hands dirty. And a few old friends who'd rather have me help them out with a do-it-yourself-er project than wait for the dealership to find time for them on their waiting list.

That plus taking-in a set of Carbs every now and again keeps me up to my eyeballs in motorcycles and old cars.

I've been having so much fun trying to get the 900 on the edge that the weeds are getting a good head start.

I always have time to help out an XJ_Biker. Ain't but a few near me and the one I did my best job on sold it for College Tuition money.
Had no problem getting top buck; either.
It was tuned-up nice.
I had to make a house-call ... but, I left with it running sweet!

 

Hey Rick, Thanks for the offer! It's good to know that there are other XJers around... and I truley appreciate all of the effort that you put into the carb cleaning article. I'm sure there are others I haven't come across yet, but I'm new to both the site, and my bike.... so give me time.

For now, I have the carbs dipping over night... I've kept the whole rack together, so am only doing two at a time (the other set will be tomorrow), and then putting it all back together after I get some bits from Chacal, and my new DynoJet kit (I've gone a pulled off the air box and am swapping in pod filters... I know... don't beat me). There might be a few other things to sort before I can hit the road (and I still need to get a permit), such as electrical, and a need for new tires. The carb rebuild was prompted by non-firing of cylinders 1 and 2 (I did have spark, and even swapped in diff coils). Disassembly revealed that the float hinges on the two mis-behaving carbs were pretty gummed-up.

So... I'd love to take you up on your offer at some point, just don't know how soon. In the mean time, wish be the best of luck and speed. Can't wait to get on the road.

 

Started re-assembling my carbs today. Found that I need another pilot screw (might as well get three... steel rather than brass makes me feel a little bit less nervous about tuning these as needed... chacal, I'll PM you), and when going through my DynoJet kit, found that one of the four jets I needed to use, which is 132, was in fact a 190! Ugh! I'll be calling DynoJet tomorrow to get it sorted out.

Also, while going through the re-assembly process, I've been taking photos which should make a nice supplement to Rick's old-school carb cleaning article.

 

Wow.....a #132 sure is a HUGE jet even for a 750. I don't know if dynojet measures and "sizes" their jets the same way that Hitachi does, but you'd almost have to be turbocharging that puppy to get that much air flow through there!

Are you sure they didn't send you a Mikuni kit by mistake? A #190 for a Hitachi carb is almost 2MM IN DIAMETER! I don't think the jets in a 4-Barrel Holley double-pumper for a V-8 Chevrolet are that large!!!

 

Yea, I don't think the DynoJet numbers mean the same as the Hitachi numbers. The kit's part number and all the documentation provided said it was for the XJ750, all model years... so I'm thinking it's correct. As for the #190... I only got one of those... and it's package was labeled as a D132... all the other D132's had the correct stamp. That 190 was visually huge compared to the others. When I get them on the phone tomorrow, I'll ask if the measuring system is the same as the hitachi's (though I doubt it).

Is there some way I cam measure the DynoJet jets to determine what they map to for the hitachis?

 

Hitachi FUEL (and fuel only) jets are coded to their mm size, i.e. a #120 jet is 1.20mm in diameter, a #132 jet would be 1.32mm diameter, etc.

Air jets, well, I haven't figured out their coding system on those, but it sure isn't the same as for fuel jets!

 

Maybe the 190 isnt a Fuel Jet?

 

An air jet perhaps? But then why would they include only one in the package?

 

Possible it's not a fuel jet, though it does sort of ave a head on it like one, where the rest of my air jets did not have heads.

I talked to DynoJet today, and after explaining my problem, with out a hint of hassle, they agreed to send out a replacement DJ132 Jet. Hope it gets here quick!

 

How nice of them.

I don't think a V-Max or a Venture run a Jet that big.
That's one for the books.

Are you sure it came in the Package? I've had some pretty mean practical jokes played on me over time.

Having someone put a Thrust Washer under your lunch bag will make you think you forgot to put that sucker in the engine.

High anxiety makes for a good laugh on you if you are the butt of the joke.