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TR4/4A Budget for TR4 engine rebuild

tdskip

Yoda
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I know the best guidance will be ballpark (at best) but assuming I have usable block, good crank, pistons are all good but I didn't actually do the work myself where do you think a reasonable range would be?
 
How does $1,000 - $6000 sound? Depends on what you want and need. If you do everything to insure a smooth running, durable engine, it won't be difficult to hit that upper number or more. The crank may look good, but could need turned. The pistons could be fine, but you may need new sleeves. The head will need magnafluxed before doing anything else to it and then the sky is the limit on throwing the money at it. Line boring, flywheel, carbs, cam and the many many necessary big and little bits don't take long to add seriously on to the total. Throw labor costs on top of all that.....
I haven't kept a running total on my TR6 engine because I've been accumulating parts for several years, and there are lots more to be purchased, but I'm expecting to be near the top number when finished. I'm doing as much of the work myself as possible, but am adding a few upgrades for durability and performance that probably make up for that savings. Granted, I have two more cylinders, but plan on the high end, and anything below that figure is a bonus.
Take your time, research what you want to do. Find a respectable engine shop and be ready for sticker shock.
 
That's a good question Tom, and I'm interested in getting opinions on it as well. For basic parts, I don't think the prices are very high:

Piston/Liner Set $500
Bearings $100
Rear Seal $100
Upper/Lower Gasket Set $100
Valves/etc for head $200
Total $1000

Minimally, just the bearings/gaskets would be around $200-$300.

Not doing the work yourself will add quite a bit - just basic machine work for the head I had a quote of around $300, full rebuild was over $1000. I think Doug's quoted range isn't out of line.

Randy
 
I found a site about a month ago that stated "Stage 3 streetable Triumph engine rebuild/upgrade $3500". I'm pretty sure it was in PA too. Sadly, I didn't bookmark the site when I saw it.
 
When I did mine, I was able to reuse the pistons and liners. All other rings and bearings were changes as well as the head was rebuilt to be a lo lead head with new valves (where needed and that was at least half of them) and new valve seats. The cost was under $1000 (just) and about half that was the head rebuild. I did all the work myself.

This is the best case in a rebuild.
 
So far I have $1500.00 in mine. That includes the machining to the crank, and head. Hot tank cleaned block and head. And the purchase of most all parts except for the rear seal. Parts can get much more expensive if you don't use the questionable parts quality of the County parts that most vendors supply. When all said and done I think I will be around $1800.00 doing the assembly work myself. That does not include any of the clutch, carb, dist, fuel pump, or even waterpump and belt. My guess would be for the whole mess to be around $3500.00 for a inexpensive rebuild. Nothing fast, more or less stock with minor upgrades. I should never add things up it always makes me think I'm "NUTS".
 
Something to keep in mind, though, just like you can either "restore" a car or simply repair it; you don't have to replace every part, every time, when doing an engine. Professionals tend to do everything, every time; but there is a lot to be said for just dealing with any gross problems, stuffing in new rings & bearings and driving it for another 30-50,000 miles. I've done it several times now; and they just keep running.

And TRactor motors are simple and rugged enough that almost anyone can assemble them successfully. Of course it's between you and your pocketbook, but if money is an object ...

And if it does go wrong, the parts are readily available. In fact, if you want a block to practice on, I'll give you one. Or PM me if you'd like to buy the entire, "running when removed" engine. I'll sell you the whole thing for less than Randy quoted for a set of pistons & liners. I'll even throw in a TR4 front plate (in exchange for the TR3 plate currently on the motor).
 
If you want a dead stock engine, I would plan on spending at least $3,000.00 for a decent one.

Sure, you could "get by" spending less I suppose, but I don't see the point of going to all the time and expense of rebuilding any 45 year old engine without covering all the bases while you're in there. For instance, failing to regrind, line bore and balance a crankshaft that is marginally acceptable, and any 45 year old crank with some milage on it will be exactly that, will result in a marginal unbalanced engine that may need to be rebuilt again within a relatively short period of time. I'm not saying you have to go overboard, like me for instance, but you really need to pay attention to the many details that will make for a smoother running, longer lasting engine that will be more of a pleasure to drive. Like the old addage states, "pay me now, or pay me later".

I hindsight, if I had just wanted to restore my TR4 to dead stock, I would have sent my old core to a reputable outfit for a completely assembled and balanced engine with a 12 month warranty. The reason I say this, is because I've already been through 2 blocks and 2 heads trying to find a decent candidate for rebuilding. Also, waiting for this shop and that place to magaflux this and hone that, or shave this, or weld that, or balace this is just the pits, especially if you don't have a plethora of very good machine shops in your area.

By the time you're done, if everything goes perfectly, which it won't, you're going to end up with at least as much dough in an engine you had to do yourself as buying one already done for around $3,500.
 
I agree with Tab.
the problem with most people that do home rebuilds, is that they don't check everything. for example:
-did you check ALL the valve springs to see that they are still at the correct rate and even rating-springs can go from 250#/in new down to 100#/in used and you can't tell by looking at them. did you check the installed height to the nearest .002"
-does your rocker shaft need replacing and do your rockers require rebuilding-probably
-what is the ring gap above and behind the rings on the pistons? it's not just a matter of looking at them and saying they look good. you have to measure them.
-do you have a full set of micrometers and guages to measure EVERYTHING accurately.
-Do you have a torque plate to put on the block with the liners in so you can take your $800 dial bore guage to see how out of round your sleeves are when torqued down?
-your cam and lifters will require a regrind if they are still serveceable
-new sprockets, chain and tensioner required (you should not put a new chain on sprockets that are worn
-rods need to be sent out for measuring (square and straight) and may need new bushings
-is your block and head square and flat?
-you will need your valves and valve seats freshened up (if they are ok)
-do you need the tops of the valve stems ground to get the proper contact pattern with your rocker arm tips.
-is your distributor shaft wobbly
-is the distributor bearing in the block worn
-do you have the ability to press out the liners, clean up the liner seats, and install F08 gaskets properly-you might need to do this a few times to get the proper liner protrusion above the block deck.


I can go on and on. Do you want to do the job again in a short while? Do you want the motor to run great.

Yup, you can do a quick freshen up, but it won't be the same.

IMHO
Rob
 
Sound like Tom has decided to change lanes in the middle of the intersection on his 71 6. He wants to be a little different. As most people stick a TR6 motor in a TR4 body ala 250. Tom is gonna stick a TR4 motor in his 71 body. :laugh:
 
I've found it has gotten more difficult year after year to get quality machine work done. All of the good machinists I've known have retired and the newer ones fall into the habit of over-complicating the list of things needing to be done - but in the end, just because they think they have brought things into specs doesn't mean they actually have. It isn't like working on aircraft engines, where equipment is constantly calibrated; and it isn't like they have education and certification standards to sign off on individual procedures. It's more a matter of them thinking they've got it nailed when they don't really have the skill, and don't understand how to set things up right. So, instead of having people who aren't really very good go through an entire engine, (with customers who don't know the difference), I have found it's far better to have them just stick to the basics. Keep it simple. Complicating things increases your risk of them overstepping their skill level. You aren't going to get a blueprinted engine anyway, so don't fool yourself into thinking that a huge list of every concealable item is going to bring about a better result. If you want a blue printed engine, your are going to stay right there in the shop - so unless you have that relationship with the shop, and already know the shop equipment yourself, just chill, save yourself some money, and don't get fancy. Pistons, cylinders, valves and cam... - and if you are going to be fussy about something, be fussy about balance. I take my time on the reassembly and work everything by hand as I go. I torque everything in steps, working the crank pistons, and then the timing by hand. If something doesn't work itself in smoothly, I stop and figure out why. By the way, I always get a kick out of checking torque wrenches with other people - and even with the shop. How about your torque wrench? Well, that's kind of a trick question, because most shops have fairly low standards for calibrating their torque values to actual standards- and it doesn't seem to matter that much, so long as they torque incrementally and equally. So, you see, in the end, you are better off just using common sense and sticking to the basics. Unless you have a super-shop that is actually capable of the detail a full rebuild requires, don't think that paying for all kinds of things that they don't know how to do well, is going to get you better result than a simple rebuild. Don't let people who name every conceivable task that can be done intimidate you. This isn't rocket science. It's a 1947 engine, about as loose as they come. You can save a lot of money by remembering that - and you'll wind up with a better result if you do.
 
I've found it has gotten more difficult year after year to get quality machine work done. All of the good machinists I've known have retired and the newer ones fall into the habit of over-complicating the list of things needing to be done - but in the end, just because they think they have brought things into specs doesn't mean they actually have.
Gotta say, this is certainly true. Only shop we could trust locally was shut down decades ago. Nearest one now is in Sarasota and they're talking about closing.

And it IS strange to see a thread being picked up after so long.
 
Gotta say, this is certainly true. Only shop we could trust locally was shut down decades ago. Nearest one now is in Sarasota and they're talking about closing.

And it IS strange to see a thread being picked up after so long.
Thanks for replying to my comments. If you have the contact information for your shop in Sarasota, I'd like to check it out. As you know, good shops are harder and harder to find.

It's nice to know there are still people out there who know what they are doing !
 
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