Page 1 of 1

Removal of exhaust manifolds

Posted: Wed Dec 26, 2018 8:11 pm
by Alpine Daimler
Hello all,

I've started on the removal of the cylinder heads, and am now down to the exhaust manifolds.

My question is can both manifolds be removed with engine in situ in my LHD saloon before I start to remove the heads?
My intention is to gain access to the block drain screws and drain the heads and block before attempting to remove heads as I don't want to fill cylinders and sump with coolant which I understand is possible and very likely!

If so I assume after the heads are refitted the manifolds can be installed afterwards?

Looks like removal of the lower steering column will help with removal of left hand manifold.

Have tried searching the old forum without luck I evetually found a short discussion on Daimler 2.5 V8 Facebook group but it is a little confusing (for me!!), clearly yet another devil of job!

Regards
Rob c.

Re: Removal of exhaust manifolds

Posted: Thu Dec 27, 2018 6:38 pm
by tjt77
It possible to remove ex manifolds with engine in car .. the deciding factor (if intent is to leave manifolds in situ) is whether the exhaust down pipe will come out of the manifold without a fight .. IF the exhaust has been replaced within the last 5-6 yrs generally they are easy to remove.. over time the downpipe and its surrounding components tend to get firmly lodged in place due to corrosion build up which can make it almost impossible and minimally VERY difficult to break loose without destroying the exhaust downpipe... you should be able to remove the block drain plugs with exhaust in situ.(r'h one just ahead of oil filter housing..L/h one just behind starter) .. they are std 5/16 spanner/ wench head.. be aware that crud build up often blocks coolant from draining.. in which case, if you have a 90' drill, run a 1/4" dill bit in the hole until you get a result (obviously do not drill into cylinder liner..this is hard to do and an unlikely scenario in any case) ..IF the coolant wont drain with the plug removed and hole cleaned out.. punch or drill a small hole on the most accessible core plug..this will allow sufficient coolant to drain below the head/bock face. thereby preventing coolant entering oil or cylinder bores.. very important to get coolant below that face, or inevitably coolant will enter the oil.. and it is not possible to get it all out without removing sump, as the it never fully drains in situ and coolant tends to float on oil.
this is NOT an enviable task.. always a dirty job..make sure you have decent eye protection to avoid getting crud in an eyeball.. good luck.

Re: Removal of exhaust manifolds

Posted: Sun Jan 06, 2019 6:55 am
by Clive
I agree the drain plugs can be removed with the manifolds and exhaust in situ. Can't remember if I removed starter motor for better access.

My nearside drain was completely blocked. I was able to clear it using a stiffish plastic irrigation tube plumbed into a hose pipe using a drilled out cork and hose clamp. This produced a high pressure jet. I was able to feed (ram, poke, jab) the tube deep into the block in different directions. Took a lot of wet work but a lot of crud came out.

Clive.

Re: Removal of exhaust manifolds

Posted: Thu Mar 07, 2019 9:45 pm
by Alpine Daimler
Hello everyone,

Thought I would answer my own question and finish off this post should anyone in the future search the title of post and need an answer.

No, its not really possible to remove the exhaust manifolds with the engine and heads in situ, I have just removed my cylinder heads and I think the following procedure is probably best and saves a lot of skin from knuckles etc!

-Remove lower steering column.

-From below the raised car treat with penetrating oil all the manifold and downpipes flange nuts/studs having first thoroughly cleaned with brass wire brush, leave for a week or so.

-Remove manifold nuts, its not difficult when using a deep reach socket and short "stubby" ratchet from above engine, manifolds flop away from heads, well, mine did.

- Release 1st forward exhaust "U-clamps" aft of flex joint close to 4 stud flanged joint, tjt77 is right the manifold/downpipe joint is most likely to be seized in and unnecessary cursing and loss of temper can be avoided by releasing this joint later with help of bench and comfortable standing position.

-Now, like me the cylinder block drain screws can be removed, using stiff wire the casting sand and diverse debris from January 1967 can be removed and the block initially drained.

Now the fun:

-1) Install oneself into a "onesey" disposable waterproof overall from the chemical industry with tight elasticated sleeves and hood.
2) Aquire and put on long rubber gloves.
3) Put on tight fitting skiing goggles and caving lamp.
4) Attach thin Irrigation watering tube firmly to garden hose using your ingenuity, mental dexterity and "thinking outside of the box" etc.
5) Now get under the car and get as much of the thin hose into the drain holes as poss, get aquaintance/wife/mistress or whatever to turn on water and wiggle it around and as far
in and out for at least 20 mins per side till all the muck comes out.


-Remove heads , in my case anyway.

-Remove exhaust manifolds and down pipes with complete ease from above.

-If not removing the heads but just the manifolds I suspect that 4 nut flanged joint will somehow have to be separated and maybe, just maybe the manifolds can then be removed from below, will be a devil of a job.

Regards
Rob C.

Re: Removal of exhaust manifolds

Posted: Fri Mar 08, 2019 6:20 pm
by tjt77
Removing the downpipes from the manifold can be a challenging proposition if they had been in there for few years .. my most recent experience of this task was that I had to cut the downpipes off with 'sawzall' just below the manifold joints..remove the manifolds with the remaining part of downpipe still attached .. and drill a 3/8" hole right through the pipe flange as close as pass to the actual manifold..fit a long 3/8 stud into the drilled hole.(I used an old BMC B series head stud) and wedge a steel chisel between stud and manifold in order to break the pipe loose from its joint.. (on BOTH manifolds) then can up the inside of the flange where the ferrule on the pipe fits in along with its seal. All in all a very unpleasant and energy consuming task.. both hands are bruised from the repeated and extended hammering that was required to get the job done..
I'd advise anyone to use a proprietary 'anti seize' compound when installing the downpipes into the manifolds.. this will make removal easier if and when the pipes need to be removed in future..