TR2/3/3A My TR3 engine is apart

[martx-5]

Well, I got it diassembled and have some obsevations and questions.

1. The scroll seal...there was absolutely NO evidence of ANY oil getting past this thing! If I can get it back the way it was, I'm not going to go for the lip type seal. Is it advisable to use the old aluminium 'seal', or should a new one be purchased. I have the tool for setting it.

2. End float was measured (with a dial indicator) before I took the main caps off. It came out to 0.009". There appeared to be one or two thou off the original thrust washers, but the wear was uneven. You can get 0.005" oversize. Does that mean that the total extra thickness is included in both sides...i.e. one side 0.0025?? And, can they be mixed with one side thicker then the other to get the proper end float??

3. Crank has been re-ground once to 0.010" under. One of the con rod journals (#1) has some SLIGHT wear in the middle where the oil holes are. I can just barely feel it with my fingernail. It should clean up at 0.020" under.

4. I have two head studs that don't want to come out using the two head nuts jammed together routine. One of them is the short (5+") stud, and the other is one of the long (9+") studs. Is it OK just to get the block cleaned up with them still in there?? I surely don't want to break off that long one. That would mean block replacement. Are there any triicks to getting them out before I send everything to the machinist??

 

[Bugeye58]

Art, can't help with the seal question. The thrust washers are sized individually, so +.005" would be for each. It's perfectly acceptable to mix and match to get the proper end float.
Let the machine shop remove the two frozen studs. I would imagine they are better set up to do it than you are, and if one breaks, they have the equipment on hand to remove the broken portion. If you want to try further to remove them, you'll need a good heat source. They are going to have to come out to do the block work.
HTH,
Jeff

 

[TR4nut]

I think Jeff is spot on but if you are determined to try it yourself, I will personally vouch for the "candle trick" that has been posted before. Small amount of heat at the base of the bolt, touch a candle to the bolt to get the wax to wick into the threads, then try to back off with the nuts. Repeat once or twice, then give up if needed.

I broke off 3 studs (2 exhaust manifold, 1 manifold attachment stud on the cylinder head) when I grabbed some parts off an old TR4a - the studs still stuck out enough to grab with a vice grips. With the candle trick it was amazingly easy to get the studs out, and I was being careful as I didn't want to shear them flush and make things worse.

Randy

 

[YankeeTR]

You can send your block in to be hot tanked/baked/stripped and the studs should come right out afterwards. Your machine shop deals with this stuff everyday.

 

[TR3driver]

If the scroll seal wasn't leaking, then chances are the aluminum housings are fine and don't need to be replaced. It's supposed to be non-contact, meaning those housings should last forever, but of course they do wear if the bearings get loose enough.

However, I've heard several sources say that the dimensions given in the manual for the "setting mandrel" are wrong and result in too much clearance (and leaks). Supposedly the tool Moss sells is even bigger than the manual specifies. The info I have handy originally came from Hardy Prentice (I think), and says the dimension should be 2.818" rather than the 2.822" shown in the manual. Hardy also claimed it is possible to use the crank itself as a mandrel, by wrapping both the rear main journal and the scroll with thread, to allow for the required clearance.

 

[Bugeye58]

And if Hardy told you that on the phone, it was a four hour call! /bcforum/images/%%GRAEMLIN_URL%%/grin.gif
Talkative chap!
Jeff

 

[martx-5]

However, I've heard several sources say that the dimensions given in the manual for the "setting mandrel" are wrong and result in too much clearance (and leaks). Supposedly the tool Moss sells is even bigger than the manual specifies. The info I have handy originally came from Hardy Prentice (I think), and says the dimension should be 2.818" rather than the 2.822" shown in the manual. Hardy also claimed it is possible to use the crank itself as a mandrel, by wrapping both the rear main journal and the scroll with thread, to allow for the required clearance.

Randall, I did some measuring today and what you say seems to be right on. The mandrel I have I got from one of the club members, and it is from Moss. It is too big. It measures 2.827". Just for the heck of it, I cleaned up the rear main bearing cap and block where it goes in and re-installed it to measure the opening on the aluminium 'seal'. (I hadn't disturbed it yet). It was a little difficult to get an accurate reading with the digital caliper I was using, but it definetly wasn't as large as 2.822" (the OE mandrel spec), and much closer to 2.818". Tommorrow I will bring home some telescoping bore gauges and a micrometer to get a more accurate reading.

Whatever, I'll be making a mandrel for this and I'm sure it will wind up close to the 2.818" figure.

BTW, you know the grooves on the side of the bearing cap where you have to pound in the Wellseal soaked felt pieces?? On mine, the last mechanic that managed to keep the rear main scroll from leaking, used silicone in those grooves. No sign of leakage. It was packed in with no gaps. It'd be nice to know what stuff he used.

 

[TR3driver]

It'd be nice to know what stuff he used.

What color was it ? IF I was going to use RTV there, I'd go for the red "high temp" stuff. It seems to also have a bit more body to it than the blue.

But honestly, I think felt and Permatex #2 works just as well as anything. And I've seen enough problems with silicone RTV that I hate to use it if there is anything else.

Just last month I had my "LBC support vehicle" in the shop because the heater blew lukewarm air at best. What they found was the core full of bits of RTV, a Christmas present from the professional mechanic that changed the water pump and used RTV as a sealer on it.

 

[martx-5]

Actually, it was kind of clear. Had no real color to it.

I'm not one that uses this stuff very much, as there are problems with it's 'overuse' winding up in places it wasn't intended. I was suprised to see it in this application, and it surely seemed to work. But without knowing what it was exactly, I'll most likely use the felt and Wellseal...or Permatex.

 

[TR3driver]

Actually, it was kind of clear. Had no real color to it.

Interesting. AFAIK, all the aftermarket automotive grades have dyes added to give them color. But maybe there is some OEM auto grade with no color added ? The "copper safe" industrial stuff we used to use was clear too.