• Hi Guest!
    You can help ensure that British Car Forum (BCF) continues to provide a great place to engage in the British car hobby! If you find BCF a beneficial community, please consider supporting our efforts with a subscription.
    There are some perks with a member upgrade!
    **Upgrade Now**
    (PS: Subscribers don't see this gawd-aweful banner
Tips
Tips

1500 exhaust manifold removal

Share this page

bigjones

bigjones

Jedi Warrior
Country flag
Offline
Happy New Year everybody!

OK, it's been determined in this <span style="text-decoration: underline"><span style="font-style: italic"><span style="font-weight: bold">thread</span></span></span> that the poxy manifold is not flat.

The good news is that it is held to the downpipe by nuts and bolts and not studs. The bad news, of course, is that I can't get the nuts off. I was tempted to see just how Husky that ring spanner is by using that pipe extension but even if it does bust it loose what about that back nut/bolt - kinda difficult to get at.

ManifoldFlange.jpg


So I'm thinking of disconnecting the downpipe/long-pipe down below (I have had that connection apart recently) and just pulling out the whole nine yards through the engine compartment. Is that possible given the bends involved?

That way I can get some Weasel Pee on the nuts and bolts.

Cheers!
 
Is there nine yards? Or is there only a short pipe where the catalytic converter used to be?
 
In looking at the photos I see that the two inner studs are missing. Is this because you pulled them, or are they missing completely. My '76 had a major vacuum leak when I fired it up for the first time. It had been sitting for 27 years when I got it. The PO had left those two studs out for some reason so the inner flanges did not seal on the intake or exhaust. They are a real pain to get to so I know he was just lazy and left them off. I replaced the gaskets, the missing and other worn studs, and problem solved. I didn't check my manifold for flatness so I can't speak to that as a possible problem. Also, the nuts and manifold ears are different (larger) on the inner two studs so make sure you have the right ones. Spritbits in CA is a good source for engine parts for the 1500's. I could find the right manifold ears anywhere else at the time. They have fair prices also.
 
JP,
Ha! No it's not 9 yards but it of course curvy and I just wanted to know if anyone had done this before I disconnected as it's a bit tricky getting that metal donut back in on re-assembly.

Rich,
I just loosely bolted the manifold back to the head so I could put some leverage on the nuts I want to remove. I've got all the proper studs and clamps. I'll probably replace the studs - Ace Hardware probably have them and I'm hoping NAPA can get the round gasket between manifold and downpipe - safe waiting on a package from Moss Motors. Thanks for the reference to Spitbits.

I'll probably start dismantling in an hour or so. Will report back.

Cheers!
 
I had trouble finding the studs locally here in the Seattle area. They have fine threads on both ends where most studs are fine on the head side and course on the manifold side.

The gasket between the manifold and down pipe is actually triangular in shape with the three bolts running through at each of the points. One word of caution on the gasket, just because you don't have a cat does not mean you need the non cat gasket. The lower flange of the manifold is bigger on the cat equipped 1500. Don’t ask how I know. If you do truly have a non cat manifold I have a non cat gasket I’ll send you on Monday.

Oh, and BTW, I had to just twist the bolts off to get my manifold and down pipe apart.
 
Well, I've spent all evening on this and the only thing I've accomplished is breaking my special 9/16" wrench (special in that it is the only wrench that will tighten them bottom manifold nuts). Total bummer.

I undone the downpipe from the long straight pipe - the assembly I'm trying to get out the car now looks like a "J", the top bar of the "J" being the manifold. I can't get the thing out because the curly part of the "J" is too long and it won't come out of the opening in the frame.

At least I can get some penetrant on the manifold flange nuts. I'll have another go wrenching on them nuts tomorrow but I'm doubtful.

I've got a little MAP (or whatever it is called) blow torch but I'm a bit weary of flames in the engine compartment.

Rich, I hear you on the fine threaded studs - let me check Ace Hardware - I just picked up some automotive studs from there (for the carb) but can't remember if they were fine-fine or fine-coarse - will report back. I notice Moss does not have the outer studs - they are shorter. Not sure what you mean about the triangular gasket - Moss lists the same gasket for the cat and the non-cat pipe.

Enough for today.
 
Moss has the studs, but you have to look at the catalog page for the 1500 head to find them. The exhaust page only shows the inner one, same with Victoria British.

As for the gasket, Moss just list one, while VB list two, but they are the same part number. Spitbits lists two different ones; it must be just a Spitfire thing. Sorry for the confusion
.
 
Rich,

Thanks for the info - didn't see that Moss had both.

Just had an idea - all is not lost - tomorrow I'll attack them nuts with my Dremel tool with a cut off wheel - unless I can fit the angle grinder in there - no more Mr. Nice Guy.

Cheers!
 
Adrian, for the studs on the head... I do have a TR 1300 engine here that we could probably take parts off of if we need to. They will be the same as the 1500. As for the cast iron manifold to down-pipe connection... I can offer no advice. My 1300 and the 1500 both had headers on them to replace the original cast iron piece so I am unfamiliar with how it attaches to the down-pipe. However, I assume the down-pipe is held on by several studs in the cast iron manifold. If you can break those nuts off I'm sure we can get the old studs out and make or find new ones for your manifold.
 
Doug,

Thanks for the message.
Sorry for the confusion - this is where I'm at this morning:

Loosemanifold.jpg


With the downpipe disconnected from the long straight pipe under the car, I was hoping to lift out the manifold/downpipe assembly - no dice, though.
Fortunately, the manifold is connected to the downpipe with nuts and bolts, not studs. I can't break them loose, however. I'm thinking of cutting through the nuts with a hacksaw, Dremel, or angle grinder - whatever will fit down there.
Will report back.

Cheers!
 
Heat.
Torch.

In the shops, when we ran into this, we'd dig out the oxy-acetylene and heat that nut up cherry red.
Let it cool a bit, soak and turn.
Or, just cut the head off with the torch, since you're going to be studding it anyway.
 
Get on those will a 6 point socket and a good open/box end, let the wrench tighten up against the pipe -and twist till they break. You will be surprised at how easy they break, or torch'em off. Finish taking that intake off and get it out of your way.

m
 
TOC.
Yeah, would have been quicker with an oxy-acetylene torch.
m,
Yeah, i got the intake out the way and attacked the bolts with the Dremel. The last one, I had to slice the nut lengthways (see pic), as I couldn't get at the bolt head, but this took a lot less time ironically, probably because the nut were not steel (or anything magnetic - or brass. Aluminum?)

Manifoldfree.jpg


Cheers!
 
I'm glad you got that off Adrian. Now we just have to figure out when to machine that flat and how to fixture it on my mill.

In the old days, some exhaust nuts used to be a bronze alloy. VW used to use them a lot, I don't remember ever seeing them on British cars though.
 
I have bolts through and a gasket in between. Never seen a donut on these, but I've only been in mine. Don't forget about what I said earlier about the 4 port gasket.
 
Kellysguy,

I was referring to the donut in the connection betwen the downpipe and the long straight pipe.

Yeah, I've already cut out the bit in the new gasket - thanks again for that invaluable information!

Cheers!
 
Took it down to the machinist and he flattened it on a belt sander for $25 while I waited (2 minutes):

Flattenedmanifold.jpg


Cheers!
 
That is much, much faster than I could have done it in. Good job and a good price!

BTW, what machine shop did you use?
 
Cylinder Head Specialists.

They are on US1 North (from 540), on the right before you get to WalMart or Wake Forest. It's a one-man shop - he's been there for ages - kinda hard to see on Star Rd - he is behind a used car dealership in a grungy building. No signs or anything. Apparently he doesn't do walk-in stuff normally - but he'll do it if you pay cash - he works on stuff from dealerships and other auto repair shops.

Just waiting on Moss now - I've ordered new manifold studs/nuts and the flange gasket.

Cheers!
 
bigjones said:
Kellysguy,

I was referring to the donut in the connection betwen the downpipe and the long straight pipe.

Cheers!
Click to expand...

Me too, no donut on mine. I have a gasket. Flat flange on both sides.
 
Back
Top