Damaged AF screw Help

[Aequitas4]

The 97 intruder 1400 I recently bought is now up and running, drag pipes, pod filters, dyna ignition, carbs synced etc. Its running pretty well but when I went to adjust the rear carb a/f screw during my tuning process I found the previous owner had left me this:



I cant tell if they have drilled through and pushed down the cap or all the way down into the actual a/f screw. Not sure if I should drill further to try and access and replace the screw or what I'm really even looking at here.

Any Thoughts?

[Designer]

Looks to me like they bungled the drilling and pushed in the Cap.

Why I say that is because you see the tiny little hole in the center of the messed up metal inside, which is what the Cap has.....and there is no evidence of the slotted recess that is in the Idle Mixture Adjustment Screw at the edges of the messed up material in the recess.

I'd say do what Herb suggested;

These are what need to be removed. On my first 1400, I drilled them with a small bit and then used a drywall screw to screw in and pull them. On the current 1400, I just used a dry wall screw and screwed it in with the power screwdriver to pull them out.

No matter which method you use be very careful because the metal is soft and you will go through it quickly. If you go too deep you will damage the needle jet head because it is soft brass. I learned this the hard way.

[Herb]

I'm the one I messed up it wasn't quite that bad I was able to get in and back out the mixture screw and get it all the way out. Then I went in then I took it and use the Dremel smooth the top off and recut the slot with one of the Dremel grinding disc. I reused the needle and it worked just fine.

[navigator]

True, they pushed the cap in.
At this point take a very sharp pointed sheet rock screw, and insert it in the small hole in the center of the brass piece.
screw it in,,,yes you will hit the a/f screw but probably not damage it.
with vice grips, wiggle and pull on the screw to extract the brass piece.
screw a little more, pull some more...repeat, repeat.
eventually you will get the brass out and expose the a/f screw.

[Designer]

All good advice there, Navigator. May I add a corollary to your experiential wisdom. If the Drywall Screw is not sharp-pointed enough to dig into and hold the existing hole he might need to make the hole bigger.

Since the Cap is SO close to the Slotted A/F Adjustment Screw Head. I might suggest he take a Drill Bit only just a tad bit bigger....Maybe 5/64ths or 3/32nds ....and use a Pin Vise Or other small Drill Chuck and do all the drilling by hand.

If a Hand-powered Chuck is not available, then I suggest put the Drill Bit into the Electric Drill and turn it BACKWARDS SLOWLY at first,...with only the slightest amount of pressure ( don't want to push the Cap in any further if you can avoid it)

Doing this will probably put a slight chamfer in the Cap Hole, and thus reduce the amount of material the Drill Bit will need to remove to get through.

Then, spin the Drill Bit forward BY HAND,...Again, with minimal pressure...letting the sharpness of Drill Bit do the cutting as it "works" it way all the way through.

Then he should be able to make any Drywall Screw perform "The Magic" you outlined for him.

[Aequitas4]

I'm the one I messed up it wasn't quite that bad I was able to get in and back out the mixture screw and get it all the way out. Then I went in then I took it and use the Dremel smooth the top off and recut the slot with one of the Dremel grinding disc. I reused the needle and it worked just fine.

Haha for a second there I thought you were claiming to be the previous owner of my bike.....I had so many questions(and choice words) until I re-read that a couple of times.

I appreciate all the replies. I will attempt this tonight and if it goes poorly I have a new a/f screw already on hand. Update to come tomorrow.

[hillsy]

Pretty hard to tell from your pic whether the cap is still in there - only thing you can confirm for certain is it's been butchered.

Maybe try spraying it with carb / brake cleaner and get some compressed air on it. Looks like theres more dirt in there than anything else from the pic.

BTW - far easier to do this work with the carb off the bike - have you had the carbs off at all? Do you know what size jets are in there?

[Aequitas4]

The picture may have not done it justice. I already cleaned out the hole as best I could with carb cleaner and PB blaster. I have had both carbs off the bike to fully clean out each orifice and install a fuel filter as many of the tiny channels were plugged. I added pod filters as well. When I saw the bike had drag pipes and the Dyna 3000 ignition I assumed it should have had bigger jets but when I pulled them all out many of the numbers were unreadable. So I took the advice of the people on this board and since I didnt know the sizes I replaced them to be sure (been lurking on here a while now). I used the factory pro 3.0 kit and have used the 165 in the rear and the 155 in the front for the mains. Both new pilot jets and new needles were installed on the 3rd clip from the top.

It runs pretty well after the carb and throttle syncing at idle and mid throttle so my thought was if it was running pretty well right now that I wouldnt try to get to the a/f screw on the rear carb due to the risk of ruining the carb. After seeing some of the responses on this forum I'm planning on trying it tonight.

[hillsy]

If your bike is running OK you are kinda lucky in that you didn't have crap in the pilot / idle curcuits when you cleaned the carbs. Bikes that sit for periods (not sure if yours ever has) will get crap or varnish in the pilot circuits and it can be hard to remove. The idle screws feed off the pilot circuit and they should always be remove to properly clean the carbs.

If you get the screw to function again and there is no noticeable difference in the idle mix when you turn it in or out the circuit is more than likely blocked. Hopefully that's not the case.

[Designer]

The picture may have not done it justice. I already cleaned out the hole as best I could with carb cleaner and PB blaster. I have had both carbs off the bike to fully clean out each orifice and install a fuel filter as many of the tiny channels were plugged. I added pod filters as well. When I saw the bike had drag pipes and the Dyna 3000 ignition I assumed it should have had bigger jets but when I pulled them all out many of the numbers were unreadable. So I took the advice of the people on this board and since I didnt know the sizes I replaced them to be sure (been lurking on here a while now). I used the factory pro 3.0 kit and have used the 165 in the rear and the 155 in the front for the mains. Both new pilot jets and new needles were installed on the 3rd clip from the top.

It runs pretty well after the carb and throttle syncing at idle and mid throttle so my thought was if it was running pretty well right now that I wouldnt try to get to the a/f screw on the rear carb due to the risk of ruining the carb. After seeing some of the responses on this forum I'm planning on trying it tonight.

Actually you did a Jim-Dandy Job with your Picture! Both Navigator and I spotted the Cap Right Away.

Good thinking about replacing the Jets with sizes you know. Your choices reflect your research of experiences of others,...always wise.

I used the recommendations of Factory Pro when I first did mine (back in 2004). I didn't have as many other guys experiences to learn from so it took me a while.
What saved me loads of time was the Temporary Tank I made. With it, I could Ride the Jetting changes without having to remove/reinstall the Stock Tank over and over and over.

[hillsy]

It runs pretty well after the carb and throttle syncing at idle and mid throttle so my thought was if it was running pretty well right now that I wouldnt try to get to the a/f screw on the rear carb due to the risk of ruining the carb. After seeing some of the responses on this forum I'm planning on trying it tonight.

One other thing - if that IS the cap pushed in on the idle mixture screw....and you get it out...pay careful attention to whether it may have damaged the threads in the port. The needle is very soft and it you try and force it out through damaged threads you will more than likely ruin the screwdriver slot and possibly jam the needle in the port.

[Aequitas4]

Thanks guys, the weather has been so nice I haven't attempted to drill the cap yet so as to make sure I can still ride the next day. I'm hoping to give it a shot late tonight and will update.

Also that temporary gas tank is an awesome idea. I went with the factory pro jet size recommendations but haven't gone through the full sizing/tuning process yet. I may have to build something similar.

[Aequitas4]

I spent a good amount of time drilling into the carb screw hole last night with no luck. At first the drilling was easy and I was able to make a small hole down the center enough to get a sheet metal screw to bite. I tried using pliers to wiggle and pull on the sheet metal screw. It felt like I had some movement but then the tip of the sheet metal screw broke off in the small hole. After that I tried to drill out the sheet metal screw and even tried to start a new hole right beside it but I'm not making progress. It feels like my cobalt drill bits are no longer biting into the material and just spin without removing any material. I even tried bigger drill bits roughly the size of the hole to just drill until maybe I could tell that I hit the a/f screw but I'm making no progress.

If you open the images you should be able to zoom in quite a bit!

It is hard to capture the detail inside the hole but everything appears to be the same color of aluminum as the housing. I haven't hit any gaps or metal that appears to be any different like part of a cap or a screw. Here's a picture for reference oh how deep I have drilled into the housing, the drill bit shows how deep I have drilled into the hole. The replacment a/f screw is also put in place for scale.


Do I need to keep drilling further?

[Aequitas4]

Zoomed in image

[Herb]

It appears that you are into the screw and it has screwed up the threads.

You might be able to back it out if you can find a reverse drill bit and work the screw out. You might check the depth of the screw on the other carb and see how far into the screw you might be. Other than that I am not sure what you can do.

[Designer]

From what I recall, the Threads on the Idle Adjustment Screw are right close to the Internal Passage that conveys the Air-Fuel Mixture to the Exit Port of the Passage. And those Threads are Much Smaller In Diameter than the OD of the Slotted Head on the Idle Adjustment Screw and Cap

Therefore,...this is nothing to even consider;

.....One other thing - if that IS the cap pushed in on the idle mixture screw....and you get it out...pay careful attention to whether it may have damaged the threads in the port.

However, even though the Enlarged Hole you just made did nothing to those Idle Adjustment Screw Threads. From what it appears, there still might be remnants of the Cap in there. In looking at the Outside Edge of the Drilled Hole, I think there is some of it left inside. I can't tell for sure if the drilling messed up the Slotted Head, but it appears it might not be damaged at all. (you can see it peeking out from under the Cap Remnants,...right in the Center of the Hole.)

[Aequitas4]

I did find a rear carb on ebay from a 96 vs1400. Should that be interchangeable?

[Herb]

Designer is correct, it does look like there is part of the notch showing. Looks like I missed that, sorry. It might be possible to get a narrow bladed screwdriver in there and back the whole works out.

[Herb]

Designer is correct, it does look like there is part of the notch showing. Looks like I missed that, sorry. It might be possible to get a narrow bladed screwdriver in there and back the whole works out.

BTW the 96 carb would work just fine.

[hillsy]

I can't tell for sure if the drilling messed up the Slotted Head, but it appears it might not be damaged at all. (you can see it peeking out from under the Cap Remnants,...right in the Center of the Hole.)

Designer is correct, it does look like there is part of the notch showing.

Are you guys looking at different pics? I can't see any of the screw showing - neither can the guy with the carb right in front of him.

Time for a new carb at this point IMO. Sometimes you just need to cut your losses.