Installing exhaust header, advice req'd & pn for temp se

[stugilmour]

I am in the process of installing a stainless steel header from Dave Bean Engineering. The header is in two pieces. The inside pipe bolts to cyl 1 & 4, the outside one to cyl 2 & 3. The Y-pipe is located horizontally at the base of the pair of S bent pipes. Car is LHD, with both brake servos still in use.

Anyway, I am having difficulty fitting the pipes in the confined space vertically. I cannot easily finesse the outside pipe past the cast piece for the thermostat and through the limited space between the frame and block. I have removed the rear servo, thermostat housing, temp sender, etc to get more room to work. I have inside pipe loose fitted in place, but I can't seem to get the outside pipe in place.

It appears if I remove the left engine mount I may be able to fit things up from the bottom. Does this make sense? Will the mount come right out of the way? If this makes sense, how should I support the engine in order to remove mount? Seems like a good time to renew the mount; is it a straight forward as just ordering up a new rubber bit and installing?

I also have one stud on cyl 3 (taking cyl one as at rear of engine) that has sheared off. I managed to get it drilled, but the easy-out has not been successful removing it. What is the max size of easy-out I can use? If the thing is truly stuck, is it possible to enlarge the hole I have (which is slightly off centre), and just re-tap the hole to the same stud size? This seems a bit mickey mouse, but i have doubts the stud is going to come out.

I am leaving one stud on cyl 3 as the original one, rather than change out to the new stainless steel ones Dave Bean supplied. It is the one under the thermostat housing, and is very difficult to get to without removing the head. The original stud is about 3/8" longer than the replacements. Will this allow me to get the outside header pipe in place, or do I have to remove this stud as well with vise grips and the like?

I have managed to break the connector off of the temp sender on the thermostat housing. I assume I can get a replacement form someone Like Moss or Victoria British; if so what car would have the same temp sender? I don't see a sender listed in the small parts price list Sue Miller sent me, but perhaps I could see if she can add one to an order I have on the go.

thx

[RotoFlexible]

Stu,

I installed what is probably the same header in an S2 recently, but the +2 should be the same in this regard. The engine mount has to come out, then it's easy to install the header from the top or bottom. Getting the engine mount back in was tricky but I eventually got it done.

I use allen-head cap screws to attach the header instead of studs and nuts. Makes it easier to get the header in place, and there is good access to tighten the screws. Unfortunately you have a broken stud so you have a problem there.

I think the engine was still attached to the hoist when I installed the header, but you could also use a jack under the sump with a block of wood to spread the load.

[andyelan]

Stu

It is a bit tricky, I spent a whole weekend without sucess before reading the workshop manual.

What you need to do is remove the left hand engine mount (with the engine supported of course) and the alternator, then feed the 2 exhaust headers up from underneath. You must feed them up together though, you can't fit one piece and then the other.

I also broke the temp sender but had no trouble getting another one from Paul Matty Sportscars here in the UK. Just watch the thread size, I think there are two different ones.

Regards
Andy

[rgh0]

Try spraying freeze spray into the hole you have in the stud to shock it free. Loctite sell a suitable spray. Gently warming the head around the stud to around 150C before you freeze the stud itself should help if necessary to free it up

In the end if you cannot free the stud you can drill the stud out totally. If careful you should be able to drill the stud out until it collapses and comes free If the threads in the head are damaged in the process then you can helicoil the hole back to size.

cheers
Rohan

[CBUEB1771]

Stu,
At the end of the day it may be best to remove the cylinder head. By doing so it will be much easier to repair the broken exhaust stud without further damage to the head. The headers can can be easily slipped into place and mounted as you replace the head. It is not difficult to remove and replace the head and you will minimize the chances of doing any further damage.

[SADLOTUS]

Hi Stu

The way I did it (addmittedly it's an S4) was to take the engine mount off and with a very stout stick/bit of wood get a friend to lever the engine over - just an inch - to get the manifold in. The engine's on a trolley jack and can be lifted and dropped to help.

Good luck.
Paul

[msd1107]

Trying to fit the exhaust over the cylinder head studs is a frustrating experience.

So the suggestion to remove the studs ahead of time will expedite getting the headers against the head.

Then allen head bolts (possibly with the proper Locktite).

Don't forget, allen head bolts save weight over studs and nuts.

David
1968 36/7988

[rdssdi]

I have installed stainless headers that were jet hot coated. It was simple as I put them on when the body was off the chassis. They did take a bit of bending ti fit properly. I did this prior to sending for coating.

I am wondering if part of my high idle water temperature is not caused by the heat from the headers soaking into the thermostat temp. sender area of the head. It would be a good idea to make up a metal (alloy?) heat shield that attaches to several of the studs and covers the header area. This should protect the boosters as well.

If anyone has done this and has a drawing, I would appreciate a copy. If not a drawing, a picture would help.

Bob

[stugilmour]

Wow, thanks for all the great advice and word of encouragement!

I will source the freezing spray and try heat from a propane torch to get the stud out. If successful, I think I will attempt the last stock stud as well with heat and freeze spray. It is sort of a "point of no return" deal though because the stubborn studs get pretty damaged during removal.

I like the Allen bolt approach a lot. I will check this out.

The supplied gaskets are a sort of metal sandwich affair with a ridge on both sides. These appear different than the stock gaskets, or at least the pouched ones I removed. What would be the appropriate torque setting for the header bolts or Allen bolts?

Hoping I don't have to remove the head, but will definitely consider options to prevent damage. I am getting a bit impatient to get finished up and get on the road again. I have to still go through out of Province inspection with a certified mechanic and take care of a few cosmetic issues when further parts arrive from Sue Miller. The car ran so well on the cross country trip, and the carbon build-up on the exhaust ports looked very even between cylinders and as very modest, so hoping I can get underway with minimum hassle.

Cheers!

[CBUEB1771]

I like the Allen bolt approach a lot.

I am not enthusiastic about the allen bolt approach simply because they are going into a soft aluminum casting and you have to worry about stripping the thread. I continue to use the studs because they really don't ever have to come out. I have only had to detach the exhaust manifold when removing the cylinder head for other maintenance.

[john.p.clegg]

Here's a thought,on the next head session should I helicoil the head and find some nice stainless allen-bolts?

John

[tdafforn]

John, not such a stupid idea...
have heard of people helicoiling all the threads on a twink head just to be sure!
Tim

[tdafforn]

Also, I agree with others. When I did my exhaust manifold (another SS, from Ebay) I supported the engine underneath using a jack and undid the engine mount. fed the manifold up from underneath and used stainless allen screws. worked a treat, although had to lever the manifold a little just to get everything aligned.
Cheers
Tim

[rgh0]

I have used allen headed set screws in the exhaust manifold in both my Elan and Plus 2 for 25 years without problems. Never had a thread strip on removal or had to helicoil.

I use normal steel not stainless but ensure they are liberally coated with nickel anti sieze before I put them in the head. make sure the threads are clean before screwing in to them.

I have never measured the torque just hand tight with a normal small allen key with about 100 mm long leverage. I use ball headed allen keys as this enables you to get into all the heads easily despite the angle required on some of them. Installation and removal much easier and quicker than with the studs and nuts.

[mikealdren]

Tim/John,
I still haven't found Helicoils that are long enough. The ones I have found have a thread length similar to a nut of the same thread size but studs (and bobbins) require longer thread lengths.

Any tips?

Mike