TR6 69 TR6 engine rebuilding basics advice

[ichthos]

Hello,

I need advice on engine rebuilding basics. I would like to concentrate on the block itself. The carbs and head have already been rebuilt. So, when you or a shop rebuilds a TR6 engine to stock standards, what is normally done? What parts are replaced? Is this something a novice could do with help from members on the forum? I like to learn to do things on my car myself, but I do not want to get in over my head. It will probably be summer before I can do much, but I thought that at least I could assess parts and buy parts I need so that I am ready to go by then. It would also give me time to find NOS parts on Ebay during this time too if I needed anything. Thanks in advance for your help.

Kevin

 

[TR6oldtimer]

Kevin, perhaps some back ground and basic plan and budget would help others help you. We know you have two '69 blocks, which may be a plus. For example, if you are not interested in keeping matching numbers, then the spare may be the starting point. I say this because it until you tear down the engine, you will not know the condition the pistons, cam, and crankshaft as well as other internals.

A case in point. My rebuild started with a '73 block and ended up with a '68 TR250 engine. Bad cam bearings and the need for a crank shaft grind on the '73 (~$1,000) caused me to drop that engine. Cylinder wear is another issue that until measured, will determine whether to bore or just replace rings. My machinist checked the cylinder wear and it was about .002. He would normally not recommend a bore of the cylinders, but in my case the piston were worn out, so if you were going to replace the pistons, then a re-bore was in order.

You have plenty of time, so planning and investigation will allow you to get through this.

Oh, these engines are not much more then six lawn mower engines in one. Not very sophisticated at all.

 

[DougF]

You will be able to do the majority of the work yourself. You can expect needing a machine shop.
A basic set of tools including a torque wrench and a piston ring compressor should be all you need.

 

[Gliderman8]

Oh, these engines are not much more then six lawn mower engines in one. Not very sophisticated at all.

Ray- I showed your post to my TR6 and he is very upset about what you had to say about his engine. He may never be the same; but then again maybe I can use him to mow the lawn

 

[ichthos]

This all started with a burnt valve. I have changed from wanting to just get it back on the road to wanting a dependable engine that will last me a minimum of 50-100 thousand miles. I want to keep my original block (numbers are correct for a 69, but I am not sure how to tell if it is actually original). The head is from my spare engine as the original was too costly to repair (the PO stored the car for years with just water for coolant and two of the ports corroded all the way to the fire ring portion of the head gasket - the engine is still fine). There is some flex in my plan. I would rather have this take a year, and raise/spend the money I need to do this right than regret things later, but I don't want to just throw money at part either. I guess what would help me out is to know: 1) What needs to be checked in what order and how do I do it so I can assess both engines? 2) What parts are normally replaced autormatically?

Kevin

 

[TR6oldtimer]

For that many miles, on a '69 this is a start.
Engine stand a must for the back.

.020 pistons and rings.
Full bottom end gasket set
thrust washer set one each std and .005
Rod and main bearings std or under sized.
Front and rear seals.
block cleaned and bored .020 oversize.
cam chain and gears and tensioner
Oil pump if needed
Fly wheel resurfaced
Clutch and pressure plate kit if needed
Clutch shaft and throw-out bearing if needed

Now it gets expensive.
Cam bearings if needed and cam bearings line bored
Cam and lifters and push rods if needed
Crank shaft grind if needed

That should just about do it.

The second engine comes into play if the crank on the original needs a grind. If the spare is within specs, you could swap the cranks. The same with the cam.

If the original engine cam bearings are shot and the spare is in fine shape, you need to make the call on originality or doing the cam line bore.

As for measuring the cam bearings, you can buy the appropriate micrometers or have the machine shop do it. I used the machine shop (does not need to be a specialist in English cars, ie lawn mower engine) My machine shop also checked the rod bearings top and bottom.

 

[tdskip]

Good info Ray

 

[ichthos]

So, is what you are telling me is I need to remove the entire block and take it to a machine shop for estimates? Would I be better off to just take both in at the same time? I admit I really hate going to the machine shop. I know I am ignorant on this subject. They just seem to get angry/impatient when I ask questions. Would it be reasonable from a machine shop's point of view for me to ask for them to inspect my engine, give me a list of what needs to be purchased, what needs to be machined or serviced, and the price for parts and services? Does anyone know of a machine shop in WA state that they would recommend? What would be a reasonable amount to be charged for this service?

 

[DougF]

Some shops are happy to talk, some look at it as money lost. Some of those may be more willing if you have a block in their shop. A lot has to do with the time of year. Right now is a good time as the race season is dying down and racers are holding off on next year's engines until the new rules are announced.

Before going to the shop, write down your questions to make sure nothing is forgotten and to make optimum use of your time.

If you don't get any shop leads from the forum, find out from your local car club. You will get other good information from there too. Clubs are a great resource for hands on learning.

 

[TR6oldtimer]

Kevin, here is what I did.

I completely dismantled the '73 block, then took the bare dirty block, pistons and rods connected in a box, the main bearings and caps in the block, the cam, and the crank shaft on the side to the machine shop. Breaking it down allowed me to lift the pieces on to the back of my pickup. (the bare block is heavy, but fairly easily lifted by me, easier when the wife saw what I was doing and helped) I also took copies of the specifications to the machinist who then checked everything. Unfortunately, the cam bearings were shot as were the crank shaft and the pistons. I had a big problem finding someone to do the line bore. So everything back home and put back together. I then tore down the other engine and back to the shop. Cam bearings fine, crank fine, cylinders and pistons at end of tolerances. So I had him bore it .020 over, after I got the new pistons.

His charges were $30 to clean the block, $270 to bore the cylinders, $25 to polish the crank, and out the door. There were additional labor charges for the inspection that he waived because I was a good customer.

His shop is a two man operation associated with a NAPA store. One machinist and one helper.

I discovered him by asking the mechanic who does my smog testing who they used for machine shop work, then went by, and for few minutes, discussed my project.

So the answer to your first question is yes, it is reasonable to have the shop inspect things, then tell you what is needed and answer whatever question you have. If they don't, you don't have to give them money.

 

[poolboy]

Ray has the same kind of guy that I deal with.
The guy knows a heck of a lot more that I ever will and was happy to give me his opinion and answer questions.
His exam was free; his opinion was not based on how much money he could make. Infact he told me that a lot of what I thought I might need in fact wasn't.
What you want is a guy who isn't depending on you to make his next car payment and someone with a good reputation..Ask around.

 

[AltaKnight]

What's the mileage on your engine?
I rebuilt mine at 52,000 miles, it was in generally good shape but oil pressure was lower than I liked.
I did it all in-situ; messy, upside down and hard work but simple enough.
I checked the crankshaft for wear and there wasn't any, I checked the bores and it was only 0.0005" wear; so no machining, just changed....
Main bearings
Rod bearings
Thrust bearings
Piston rings (kept the pistons)
Honed the cylinders to break the glaze
Cylinder head and valve gear was all good so didn't do anything.
And that would keep the motor going for at least another 50K miles....

however, wanted MORE POWER!

So machined the head 100 thou to raise the compression (to about 9.0:1)
Changed the camshaft to a TH5 from BPNW
New tappets
Shorter pushrods (because of the machined head)

Put it back together and I've got 3,000 miles on the rebuild, oil pressure and performance far, far better.

Moral of the story, you can do as little or as much as you want, it's just money, time and busted knuckles; BTW it's fairly straightforward but you do have to keep things clean during the surgery!

 

[DNK]

Kevin - i know it is a long way but Autosport in Seattle should do you fine. They won't make you feel like an idiot and will only do what you want and will help you decide same.

 

[Brosky]

If you want to see everything that Ray and the others described as it should be done once it's at a machine shop start here:

TR6 Block Machining

If you follow my pages, you'll have a pictorial guide as to exactly what you MAY need done and you can see what the shop should look like that will be doing your work, along with how it's done. There are several pages that show the entire engine rebuilding process on the left side of the pages.

Good luck!!

 

[danstr6]

Kevin,

My advice. Double your estimate on time and money. Get your engine balanced while at the machine shop. Replace any internal part even suspect of showing wear. Buy your wife something nice for putting up with this.

Check out my engine rebuild photos at: https://www.luvmytr6.com/page2/page2.html