d.p Posted November 8, 2017 Report Share Posted November 8, 2017 Man it just snowballs with these trucks lol. Welcome to the club. 1/4” BPST? I say that cause I just plugged my intake manifold with one. maybe easier to just retap? How hard was it get those EGR bolts out? Mine are frozen along my down pipe flange so I can’t even take my exhaust manifold out of the truck. Quote Link to comment
mainer311 Posted November 8, 2017 Author Report Share Posted November 8, 2017 The upper EGR bolts came right out. The studs on the other hand... I got one out so far. It took a lot of heat. I’m saving the other two for tomorrow. 1 Quote Link to comment
wayno Posted November 8, 2017 Report Share Posted November 8, 2017 The upper EGR bolts came right out. The studs on the other hand... I got one out so far. It took a lot of heat. I’m saving the other two for tomorrow. Get it orange around the base of the stud(don't heat the stud), then hit the side of the manifold near the stud with a hammer, then turn the stud out with vice grips. 1 Quote Link to comment
mainer311 Posted November 8, 2017 Author Report Share Posted November 8, 2017 Yeah, that’s what I did. A propane torch only gets you so far though. One of them successfully came out, just took some time. Hoping I can find the thread size on the manifold plugs today. 1 Quote Link to comment
Crashtd420 Posted November 8, 2017 Report Share Posted November 8, 2017 Yeah, that’s what I did. A propane torch only gets you so far though. One of them successfully came out, just took some time. Hoping I can find the thread size on the manifold plugs today. There is a good chance they are bspt threads... since you have the manifold off easiest thing to do is retap the bspt with an npt tap... npt plugs are alot easier to find locally.... 1 Quote Link to comment
mainer311 Posted November 8, 2017 Author Report Share Posted November 8, 2017 They aren’t tapered. If you look at my picture, the compression happens at the flare on the end, like a brake fitting. There’s a second tube protruding through the manifold that has the female flare on it.Best I can tell, it’s an M14 fine thread. It VERY closely matches a 1/4 NPT, but the threads don’t line up. I’m going to see if I can get a measurement on the threads and then order some short bolts with copper washers. EDIT: Just did the conversion. 1/4 NPT is 18 TPI, which works out to a metric pitch of roughly 1.4. .1mm is practically nothing, so I'm assuming the thread is an M14 x 1.5. This would account for the threads being slightly different. 1 Quote Link to comment
mainer311 Posted November 8, 2017 Author Report Share Posted November 8, 2017 Also, it turns out that M14x1.5 is basically the same thread size of an oil drain plug. 1 Quote Link to comment
Crashtd420 Posted November 8, 2017 Report Share Posted November 8, 2017 You would be surprised how slight the taper is.... On a 1/4 npt thread gauge along the length of the thread there is Only a .020 difference.... Do you have any measuring calipers? You can't really see the taper.... 1 Quote Link to comment
mainer311 Posted November 8, 2017 Author Report Share Posted November 8, 2017 I just checked with the Datsun Roadster guys. It's an M14x1.5. I can assure you, there's no taper. You don't want the threads to lock up before the flare gets compressed. With that said, since the tubes are removed, jamming a 1/4 NPT plug in there would probably work, but I heard the fit isn't very tight. 1 Quote Link to comment
Crashtd420 Posted November 8, 2017 Report Share Posted November 8, 2017 All good.... better to be sure... 1 Quote Link to comment
mainer311 Posted November 8, 2017 Author Report Share Posted November 8, 2017 Just measured. This 1/4 NPT plug I bought this morning measures 12.96mm on the tip to a max major diameter of 13.25mm. So you're right, the taper is minuscule. The EGR tube nut measures 13.8mm along it's entire length. 1 Quote Link to comment
Crashtd420 Posted November 8, 2017 Report Share Posted November 8, 2017 These trucks are pain in the ass with all the different thread types.... Once you realize it it's not so bad but it has caught me off guard a few times... 1 Quote Link to comment
gene knight Posted November 9, 2017 Report Share Posted November 9, 2017 here is what i did to my manifolds, sorry for the pictures i just took them. i can't remember the thread size https://s1.postimg.org/2vqunbf60v/exhaust_manifold_plug_1.jpg https://s1.postimg.org/8b24jwzbnz/intake_manifold_plugs_1.jpg 1 Quote Link to comment
mainer311 Posted November 9, 2017 Author Report Share Posted November 9, 2017 Thanks. I ended up using some oil drain plugs and aluminum washers. I had to angle grind a little bit of clearance for the flanges on the bolts. I’ll spray the whole thing with high heat paint tonight. Quote Link to comment
d.p Posted November 9, 2017 Report Share Posted November 9, 2017 Post a pic. And what size/thread plugs? Quote Link to comment
mainer311 Posted November 9, 2017 Author Report Share Posted November 9, 2017 M14x1.5 I'll get the picture up tonight. It's definitely not as clean looking as allen-head plugs would be, but it's not horrible. Once I get paint on it, you won't even really see them. 1 Quote Link to comment
mainer311 Posted November 10, 2017 Author Report Share Posted November 10, 2017 Here’s a pic after high heat paint: 2 Quote Link to comment
d.p Posted November 10, 2017 Report Share Posted November 10, 2017 Looks good to me. Did you have retap those egr holes? Quote Link to comment
banzai510(hainz) Posted November 10, 2017 Report Share Posted November 10, 2017 high temp powdercoat is the best as all paint wears off 2 Quote Link to comment
Stoffregen Motorsports Posted November 10, 2017 Report Share Posted November 10, 2017 There is one "paint" that doesn't wear off, but it is so poisonous that I won't even mention it for fear that someone will run out and try it for themselves. 1 Quote Link to comment
mainer311 Posted November 10, 2017 Author Report Share Posted November 10, 2017 Looks good to me. Did you have retap those egr holes? Nope. It’s M14x1.5. You could chase the threads if you wanted to, but mine were very clean to begin with. I know the paint won’t last, but it’ll look okay for a little while. 1 Quote Link to comment
Stoffregen Motorsports Posted November 10, 2017 Report Share Posted November 10, 2017 Nope. It’s M14x1.5. You could chase the threads if you wanted to, but mine were very clean to begin with. I know the paint won’t last, but it’ll look okay for a little while. When using heat paint, it helps to heat the metal you're painting before the paint goes on. Not red-hot, but hot to the touch. It burns the paint on giving it a head start and will last longer this way. 1 Quote Link to comment
mainer311 Posted November 10, 2017 Author Report Share Posted November 10, 2017 Got it all back together. Cleaned all the junk out of the carb in the process. What’s the sensor switch that closes when the throttle opens all the way? And I’m assuming the large round solenoid on the side is the anti-dieseling? 2 Quote Link to comment
banzai510(hainz) Posted November 11, 2017 Report Share Posted November 11, 2017 I love it 1 Quote Link to comment
Stoffregen Motorsports Posted November 11, 2017 Report Share Posted November 11, 2017 Can't help you there. I know virtually nothing about the stock carbs. Looks nice and clean. 1 Quote Link to comment
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