Stag Stag automatic

[Got_All_4]

Been looking at a Stag that is in decent shape. Looking for a reason to just go get it but is't 5 hours away and I'm no Stag expert. Paint looks nice, all the parts are there, some surface rust but there in hole in the floor boards near the rubber plug. Under the rear seat looks good too. One of the reasons I'm even thinking of it is that it is automatic. Preparing for the future as these old bone and joints are failing. Also the wife would be more incline to drive it although she can drive a manual better then a lot of men.


Talking to my sometime Triumph mechanic who is just completing a mechanical Stag restoration he thought they were pretty robust trannys and built by I think he said Borg Warner and were used in Volvo's and other European cars at the time. So that is one of my questions. It is also a 3 speed gearbox and concerned about fuel millage as it will be my daily driver for retirement. Next is he thought there would be a lot of Volvo 4 speeds out there available for a swap and a up grade. The guy is asking $4700 for the car. What do you think?

 

[TR3driver]

Yes, early Stags got the Borg Warner BW35; later on they used the BW65 (but I think that was after they stopped importing to the US). As noted, they were used in a lot of cars and AFAIK had a good reputation. Repair parts seem to still be readily available.

I've not heard of any easy tranny swaps to the original motor, but that doesn't mean much.

With 14" wheels and the 3.7 rear axle, the engine turns pretty fast on the freeway. I think that's part of the reason fuel consumption is so high. I averaged about 20 mpg in mixed city & highway, with a manual and OD. IIRC it was around 24-25 with sustained freeway driving. That's also the earlier US engine with slightly higher compression. Since the BW35 has neither overdrive nor a lock-up torque converter, I would expect to get somewhat less with it. The later Stags also lacked vacuum advance, which will also burn more fuel (but can be corrected).

The Stag's Achilles heel is the engine. Prone to overheat (for multiple reasons) and the aluminum heads are easily ruined by overheating. New ones are not available of course, and salvaging old ones by welding them up and re-machining can run into a lot of money. The cams run right in the head casting (no bearing inserts), so any warpage or damage to a cam bearing means having the head line-bored for bearing inserts. Normal rebuild parts are available (tho sometimes only in Euro-spec), but prices are high and quality is dubious. Just parts and machine work for a rebuild can easily run more than what you are talking about paying for the car.

I bought a Stag in perhaps slightly better condition, less than 80,000 miles on the odo, with the intention of using it as a daily driver. Worked out OK for a few years, but I forgot to keep an eye on the gauge and it overheated on the way home from VTR in Rockford IL. Sure enough, one or both head gaskets is leaking compression, and the studs are locked into the heads. I plan to build an EDM machine just to get the studs out without ruining the heads!

Bought another to drive while I worked on the first one, but had so much trouble with it that I never found time to work on the first one. Now they're both broken, and it's not clear I ever will get back to working on either of them!

I'm not saying it can't be a good, reliable car; just that the odds seem to be against it. The experts at ISOA built one to sell for charity, and I understand it has held up very well. But many if not most of the Stags that are still around no longer have the Stag engine for a good reason.

 

[Got_All_4]

Thanks Randal and sorry to hear of all your troubles. Whats a EDM machine? I heard of all those engine problems. The owner said it needs a little tuning as there is a slight miss or rough running. Has duel points and said he thinks that's where the problem is. He wants to put some type of electronic ignition in it and thinks that would cure the miss. He runs a LBC repair shop and I would think it would be done before he would try to sell it. Admitting that I'm not an expert on these cars and knowing their history I'm talking with my Triumph mechanic to see what he would charge me to go and evaluate it with me. Would have to do everything in one shot including bring it home because that's 10 hours just in drive time.

Every car around here I've seen has had some kind of engine swap. Most with Chevy 350s. One had a Buick 236 that had a off set carb and the owner had to do some extensive mods that looked hokey at best. If this engine is ok I was reading about installing an over size radiator to help cure the over heating problem. Also watched an episode of Wheel Dealers redo a Stag and ED did that very thing. I like the fact too that this car is in very original condition and all the parts are there.

 

[charleyf]

I owned a Stag for a couple of years. Loved the look -- but the engine was frozen and all the study I did told me that I could pour a lot of money and time into that engine and still have an engine that I would have little confidence in. So I sold it. The body was totally solid. I sold it for what I bought it for, which was $7500.
one interesting engine swap that I learned more about after I sold the car was the TR6 motor. Had I kept the car I do believe that would have been my prefered engine.
Charley

 

[TR3driver]

EDM stands for Electrical Discharge Machining, also known as "metal disintegration". https://en.wikipedia.org/wiki/Electrical_discharge_machining
Somewhere, I've got an old magazine article showing the construction of a "portable" version, and the author's use of it to remove a seized and broken head stud from (IIRC) an aluminum snow blower motor. Here's a less portable version, used to remove a small broken tap from a tiny aluminum engine:
https://modelenginenews.org/~modeng74/meng/edm/index.html

I should add that this is by no means the only way to remove a stuck Stag head (or TR7 which is the same problem). Several folks have come up with a puller tool (I'm not sure who to credit for the original idea) that reportedly works very well. Here's a link showing the TWOA version https://www.triumphwedgeowners.org/head-honcho-in-action.html

A friend let me drive his Stag that had been re-engined with a Buick V6 and 3 speed automatic (not sure offhand if it was the original BW35 or a similar unit). Very sanitary conversion, but to me the pushrod motor never seemed happy at freeway speeds. Roughly 4200 rpm at 75 mph.
In retrospect, I probably should have bought that car (it came with the original motor ready for rebuilding), but I decided I wanted overdrive.

 

[Got_All_4]

Randal you may recall all the trany and OD questions I had over the last couple of years. Well last year they all paid off as I got the OD trany into the TR3A and o what a difference in the driveability. I am now going to put one in the TR250 and if I keep the 69 TR6 one for that too. So I don't blame you for holding out for a OD.

I always wondered if anyone ever tried to do a Volvo engine and trany swap in one. Could be a great upgrade. I had a 1987 740 turbo and was one of my favorite all time cars (not including the Triumphs of course). It had 356k on it when I sold it to one of my neighbors and it still had the original turbo charger in it. That turbo sure woke up the B23 motor.

 

[StagByTriumph]

Re: Stag automatic - Cylinder Head Tool?

Hey Randall,

I have the Head Removal bracket tool in my garage, pulls any Stag or TR7 head with zero added damage. You pay round trip shipping to get it if you promise to turn it around in a few weeks.
The tool has been used on dozens of engines, works even with broken and fully seized head studs.

Typically it only takes 1-2 hours per side considering unpacking, setup, pull, change sides, repeat, then clean up the all-thread ends for the next use and repack.
When you have the top end engine parts clear, call me for the shipping details for supplying the label and I will ship it off to you. It works best with the engine out, but if you pull the brake booster and booster vacuum accumulator, you can pull the heads with the engine in the car.

BTW, we have several Stags running around with solid copper head gaskets, thickness is custom adjusted when made to compensate for head skimming to restore back to OE head heights.
The Motorway in Ft. Collins had the pattern copied from a new OE gasket I supplied at https://www.cometic.com The gaskets are available in the standard configuration right now, when I get a RoundTuit, I will do one that covers the exposed aluminum water jacket block side exposure from where the OE gaskets have too large of holes not matching the head. these are available in a range of thicknesses for about $160 a set. They should still have the pattern in their system, and Frank at the Motorway says the fit was perfect. You anneal (soften) them with a propane torch, cool, then spray evenly with copper tack sealant.
Nice thing about these is, you reuse them if you remove the heads in the future. Of course, having a 90 degree square intake manifold to 90 degree cylinder head intakes with correct intake gaskets is important before bolting everything to torque.

 

[TR3driver]

Thanks, Glenn. That's my backup plan (but I still think having a working portable EDM would be cool).

But I'm a long way aways from being ready to work on it again. The TR3 has a broken crank, and I want to deal with that first. Then I have to finish pulling and rebuilding the gearbox for Stag #2, so I can get it out of the way and get Stag #1 back into the garage.

But for the next few months, I'll be away from my garage and not working on any of this stuff. Might get Dad's TR3A back on the road though, if all goes well.

Any BCFers going to the Kastner Cup race in a couple of weeks? I might see you there.

 

[JerryVV]

Any BCFers going to the Kastner Cup race in a couple of weeks? I might see you there.[/QUOTE]


Yep