Joined Apr 18, 2013
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2,615 Posts
Joined May 14, 2016
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137 Posts
Discussion Starter · #3 · Oct 31, 2016
What they use on this engine. Both Sae and metric.
Joined Jun 10, 2015
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3,324 Posts
They have knurls on them like a wheel stud (assuming you are talking about the manifold to down pipe flange bolts). The nut should spin off, while the head of the bolt stays still. I got one bolt off and cut the other with a right angle air wheel. Stainless steel 3/8 bolts are in there now.
Joined May 14, 2016
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137 Posts
Discussion Starter · #5 · Nov 2, 2016
No. rear manifold bolt in head. Does it look like it's been broke off in there???
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Joined Apr 18, 2013
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2,615 Posts
Looks like it hasn't been there in a while and rusted over a bit
Joined Jun 10, 2015
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3,324 Posts
Yeah^^^ Cutting oil and a tap should clean the threads up. BE SURE you get the correct thread of tap. Compare it to the other bolts that came out.
Joined Apr 18, 2013
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2,615 Posts
3/8-16 is the thread tap you need....
Joined May 14, 2016
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137 Posts
Discussion Starter · #9 · Nov 2, 2016
When we bought it back in May it must have been like that. Just noticed it gone other day. But has had exhaust leak since we have had it. Just hope it wasn't broke and they tried to get it out.
Joined Feb 10, 2017
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909 Posts
how about the length? anybody know what size the bolts are for '95 YJ 2.5L? I need to replace exhaust manifold and would like to have correct size (length, diameter, and thread pitch) before I remove the old ones. I intend to replace them all. FSM gives torque sequence, and spec., but no dimensions.
Thanks
Joined Apr 18, 2013
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2,615 Posts
how about the length? anybody know what size the bolts are for '95 YJ 2.5L? I need to replace exhaust manifold and would like to have correct size (length, diameter, and thread pitch) before I remove the old ones. I intend to replace them all. FSM gives torque sequence, and spec., but no dimensions. Think many people prefer 2 inch studs
Thanks
Joined Jan 14, 2014
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15,991 Posts
According to the factory parts catalog, the pic that the OP posted requires a stud. One at the rear and another at the front of the manifold. P.N. J400 7462 (2) I can't see any problems with the studs being too long, but I don't have a 4cyl engine. If they're too long, you can cut them shorter with a die grinder or Dremel tool once the manifold is in place and tight. Good Luck, L.M.
There is a spacer required on each stud P.N. 3300 3332 and then each stud gets a washer P.N. J317 3077 and a nut P.N. J400 7153.
The washers and nuts are probably standard hardware,.
The studs are probably standard hardware too. I think the spacers are to center the manifold over the openings in the head to help prevent exhaust leaks.
Joined Nov 21, 2013
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34 Posts
What about the heavy cupped washers? My 2.5L manifold had them under the bolts, but is missing one. The Dorman 03048B manifold bolt kit from Summit racing includes the bolts, studs and 2 spacers + 2 washers and nuts for the studs, but there are none of these heavy steel cupped washers. Do I need them? Know where I can get a couple?
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Joined Jul 15, 2017
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111 Posts
Joined Jul 15, 2017
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111 Posts
Joined Feb 10, 2017
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909 Posts
Joined Nov 21, 2013
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34 Posts
Thanks guys! I've got a couple of washers on the way. Didn't not find them searching by XJ model, but came right up with the link. again, Thanks! I've posted another question on a separate thread but so far no responses... I am planning on replacing the manifold bolts with Stainless steel. A recommendation from the Engine machinist who reworked my block
and head. I'm no metallurgist, but it sounds like stainless would be better. Does anyone have an opinion on using stainless manifold bolts?
Oh, and another question - can you tell I am on my first rebuild? - is using Never-seize okay on these manifold bolts?
Joined Feb 10, 2017
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909 Posts
use never seize. if you use stainless hardware, make sure it's the same grade (or better) than the original hardware. them 2 little lines on the head of a stainless bolt only means that they're stainless, not graded. you won't find them at Lowes, or the corner store. McMaster Carr carries them, but they ain't cheap. if yer not familiar with different grades of
fasteners, do a little research before you start making changes to what you have.
Joined Jan 14, 2014
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15,991 Posts
I'd just use grade 8 regular carbon steel bolts and Anti-Seize (Never Seize). Good Luck, L.M.
Torque specs drop a bit when lubing bolts, but I don't know by how much.
With grade 8 bolts, I'd just torque them to published spec.
Joined Feb 7, 2018
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34 Posts
Any one know what size bolts are in the 91 yj 2.5L. I saw your pics looking straight into hole and it looks to me like it was broke off inside and an attempt to drill it out failed and looks like its filled with JB Weld epoxy , is that possible , did you buy with this already done . I just had to take
out two broken inside head hole unevenly and it was a chore to say the least. I don't know if your YJ 2.5 is same as my 2001 wrangler TJ 2.5 but the front and back bolts on exhaust manifold are studs with a spacer that centers the alignment of manifold the wrench size is 14 mm I can get the size of bolt I think it was 9/32" but Dorman has mounting hardware kits for it and tells the size so might check them out . The spacer is important so I would put those back in and you can tell that it had
them by the difference in those two holes on manifold they are larger than the others in diameter.