YAGT (Yet another gauge thread)

[BGlidewell]

I'm installing gauges this weekend weather permitting. I've read and researched this site on the details of tapping, boost bolts, trans-cooler hose adapters, grease or no grease, engine running or not, 1/8 or 1/4 pyro, wire taps, A-Pillar/dash and color codes etc.



I have pestered a few people at work too and my fine-feathered-ford-friend told me I could use a shop-vac in blow mode at the tail-pipe to put positive pressure on the exhaust system while drilling and tapping the pyro hole. I never heard of this technique... he also said most people use too much speed and not enough pressure or too much of both when drilling and too many revolutions of tap before backing out chips. Low speed moderate pressure and back and forth revolutions with the tap feeling for the cut and chip sounds like the way to go. Not to worry so much about debris as the velocity they would have and their size would not have any impact on the turbo and the most critical concern would be that I not break off a bit or tap in the manifold.



Another guy said water is the best lube for drilling cast iron and all I need is a little spray bottle of water to wet the bit. hmmmm.



I could not find a NPT tap at Sears or Home depot so I went to Graingers and they must have known I was coming. It cost me almost $60 for two taps ( 1/8 and 1/4") and three bits, (they're reference chart says 1/8th NPT requires a Q bit so I got a Q and an R) For those who plan better than me,



http://www.dieselmanor.com/dm_products/TAP1418.asp



seems to be a good deal, and they have a great page of instructions.



I may find a piece of scrap cast iron to practice on first...

 

[nick05]

don't sweat it too hard man. once your done you'll be saying man that was easy. (hopefully;at least my case). but if your concerned with drilling the cast iron don't be. i work with it every day porting cylinder heads at the race shop. DON'T USE WATER. doesn't lube worth a darn for the drill. just center punch the hole where you want it so the drill don't walk. i've heard of guys coating the drill bit in grease or vasoline so the shavings have something to stick to. i just drilled the hole in mine and stuck a magnet down in to get what i could. then use tap fluid or grease on the tap to cut well and collect the metal. tap and check every few turns so you don't tap too deep. other than that, put the plug in, connect wires and fire it up.



i'm no expert but i do know a little. and learned.

 

[Cattletrkr]

No grease, engine off, vacuum sucking while drilling and a magnet afterwards. I use a punch to mark the hole and an itty bitty bit for a pilot. I've done 4 with no probs. Cast is easy to drill and tap. I've never worked with it other than the probes and it's a snap.

 

[robmints]

The diesel manor instructions worked just fine for me. I used no lube of any kind and vacuumed from the outside right at the hole. Taped a piece of tygon to the shop vac and taped the tygon to the manifold so it would suck right at the spot I was going to drill. If you blow air up the tailpipe could the shavings blow into and open exhaust valve and into the cylinder?



The only thing I did different than the diesel manor instructions was it says to step up in drill size one size at a time. I did not do that. I drilled it in about 5 steps up to a T drill. I think it was a T drill, the tap was way too tight after a Q. I think you want to tap the hole so the tap goes in about 2/3 the length of the thread on the tap. But you should stop about 1/2 way in an check your fitting. If it does not go in far enough, tap some more.



I sure did find my 90 degree drill motor handy for the drilling though.



Make sure you drill in the correct spot, there are some good pictures around here of the good spots to drill.

 

[SNoyes]

I've put in my fair share of pyros... . 3 Strokers, 3 Cummins now... Most effective I have found was starting small and working my way up to the larger bit. The most effective for drilling is one of those standard bits, I bought one of those super hard bits and had it shattered on me... . sweet let me tell you... As for removing debris. Well, haven't dusted a turbo yet. I use a tool magnet to pull out most, a shop vac to get the rest.

 

[BGlidewell]

The diesel manor instructions worked just fine for me. I used no lube of any kind and vacuumed from the outside right at the hole. Taped a piece of tygon to the shop vac and taped the tygon to the manifold so it would suck right at the spot I was going to drill. If you blow air up the tailpipe could the shavings blow into and open exhaust valve and into the cylinder?

The only thing I did different than the diesel manor instructions was it says to step up in drill size one size at a time. I did not do that. I drilled it in about 5 steps up to a T drill. I think it was a T drill, the tap was way too tight after a Q. I think you want to tap the hole so the tap goes in about 2/3 the length of the thread on the tap. But you should stop about 1/2 way in an check your fitting. If it does not go in far enough, tap some more.

I sure did find my 90 degree drill motor handy for the drilling though.

Make sure you drill in the correct spot, there are some good pictures around here of the good spots to drill.

Good point on the valves using that method.

Yes the step up in every drill size seemed a bit difficult because the bit will want to screw in if it does not have a backward resistance and a bit of work for the tip of the bit to cut.
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I'll have to dig up some of this and try it for the vacuum. Thanks!

don't sweat it too hard man. once your done you'll be saying man that was easy. (hopefully;at least my case). but if your concerned with drilling the cast iron don't be. i work with it every day porting cylinder heads at the race shop. DON'T USE WATER. doesn't lube worth a darn for the drill. just center punch the hole where you want it so the drill don't walk. i've heard of guys coating the drill bit in grease or vasoline so the shavings have something to stick to. i just drilled the hole in mine and stuck a magnet down in to get what i could. then use tap fluid or grease on the tap to cut well and collect the metal. tap and check every few turns so you don't tap too deep. other than that, put the plug in, connect wires and fire it up.

i'm no expert but i do know a little. and learned.

No grease, engine off, vacuum sucking while drilling and a magnet afterwards. I use a punch to mark the hole and an itty bitty bit for a pilot. I've done 4 with no probs. Cast is easy to drill and tap. I've never worked with it other than the probes and it's a snap.

Appreciate the encouragement and tips. Thanks!

 

[TJJEEPER]

Greasing the drill bit and tap worked fine for me. Somewhere I read to idle the engine a bit after the tap job to blow the fine stuff left over. Did that too. No problems what so ever. Go slow and clean often.

 

[JMarketos]

I'll echo same comments as most above.

After lots of nail biting and perspiration, a very experienced person

told me just don't worry too much about it. At startup,

the turbo isn't moving and the exhaust flow is low, and all

the worries about grenading a turbo are way overblown.



I drilled using one single large drill bit and my heavy duty

craftsman 1/2 inch 110V drill. I didn't use any oil lube during

drilling, but took it slow (used time rather than heavy pressure).

I did make sure to use a quality drill bit that was sharp.

The big cast iron manifold can absorb lots of heat if you don't

treat the drill like a punch... .



For tapping, I used some grease to catch shards, though this may

have been a waste because I didn't do that when drilling. It is important

not to turn the tap forward too much without backing, and be careful

not to put side stress on the tap, so you don't break it off in the hole.



Remember- for the whole drilling process until you break through

the inner manifold passage, no metal gets into the manifold and

you can stop and vacuum the shards all away. It's only at the very end

and during the tapping process that you have the possibility of

metal shards entering the exhaust path.



I then used the vacuum cleaner with a little piece of tubing.



That was thousands of miles ago, no problems.

 

[DShore]

Use cutting oil or gel on sharp drill bits in 2 or 3 steps with a fairly slow drill speed will usually make metal come off the bit with a nice curl out of the hole.



On the tap use LUBRIPLATE or moly grease, etc. , that is tacky. Regular axle gease is too stiff to attract the chips. Generously coat about 1" of the tap. Don't get in a hurry. Install pyro, start it up, idle 5 minutes and go.



This also works when putting thread inserts in stripped spark plug holes on engines without removing heads.

 

[BGlidewell]

Use cutting oil or gel on sharp drill bits in 2 or 3 steps with a fairly slow drill speed will usually make metal come off the bit with a nice curl out of the hole.



On the tap use LUBRIPLATE or moly grease, etc. , that is tacky. Regular axle gease is too stiff to attract the chips. Generously coat about 1" of the tap. Don't get in a hurry. Install pyro, start it up, idle 5 minutes and go.



This also works when putting thread inserts in stripped spark plug holes on engines without removing heads.

I picked this up at Graingers along with fresh 3" long drill bits to go in my 90 degree cordless drill motor:

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[donnier]

IMHO, the idea that F_()* owner gave about blowing up the exaust explains their mentality. :-laf

 

[BGlidewell]

The Diprocol EGT temperature gauge does not return to zero at engine ignition off, but remains at the reading when the engine switched off. At restart, or key-on after cool-down, it returns to zero. Is this normal?

[edit: I got my question answered by calling Danin. This is normal. ]

Overall, the install went well. The EGT probe was easy. Most aggravating was the 4 hours spent looking for a missing 1/8th compression fitting. Those things are not readily available!