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62 / BT7 tri-carb engine

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well i have about run thru everything i can and only have the eingine left to get back in the car. since i bought the car in boxes, i have never heard the engine run. So i have no idea what i have there. hoping for the best.

i am reading, and re-reading, the Bentley book. looking for any video i can find and searching the internet for any info and help on what to look for or be careful of as i take this engine apart. if you all have any tips or suggestions, please send them on. i hope to start this week once i finish up painting a few parts and taking care of a few misc things.

DSCN0296.jpg

Thanks
 
If its worn out replace it , if its broken replace it , dont cheap out on the engine rebuild . Nothing special about a Healey engine its just a big cast iron lump of a tractor engine .
Do it right the first time and it will run forever with regular maintenance and oil changes .
 
You're pretty close to Healey Surgeons if you get into trouble on the rebuild. On mine, once the head was off, Russ Thompson pounded a long phillips screwdriver down the rearmost coolant passage (between the block and head). Dirt gets impacted in there and must be broken up for the hot tank to do its job. There's some issue with the alignment of the camshaft vs the distributor drive you have to be careful of.

I could see disassembling it yourself, but would sure want an experienced person to supervise or at least check the machine shop work. My rebuild was about $8k parts and labor.
 
i talked to the healey surgeons about the engine one time when i was ordering parts from them. they told me in the 40 years, they maybe rebuild 2 engines a year. they talked about how sturdy these engines are and thought i should try it before any rebuild. they said a rebuild is all or nothing and costs about 8k. so they would put it in, fire it up, check the compression and oild pressure. if it was good, they would leave it alone.
i just don't want to put the engine in only to find it has to come right back out for something. So i figured i would at least look it over for any obvious signs of problems.
 
These engines are very sturdy and reliable . The minimum I would do would be drop the sump and check the mains ,pull the head and have the valves re done and new valve guide seals . Check the oil pump for wear while your in the sump .Redo the timing cover seal and check the cam chain and tensioner while its open and seeing as you have the head off you may as well put a set of piston rings in it .
obviously if you pull the sump and head and find the bores scored and the sump full of metal shavings then your going a lot further .
Or you could do nothing but a compression test and if thats good fire it up and see what happens .
 
well i started the tear down today. Nice to have the engine on a stand. a little aurprised by so much carbon on the pistons.

but the cylinder walls looked really clean. i expected to see some scores there but i did not. Also a little surprised to see the red on the intake valves. would have thought that would have burned off before now. cleaning up and separating everything at this point. certainly there is some gunk.

my valve compressor would not do the job to release the springs so i need to find one that will. tomorrow i plan to pull the oil pan off and then decide where to go from there. IMG_0259.jpgIMG_0260.jpg

the first two pistons had a "TM" marked on them plus a "3" in a diamond. the other four pistons had an "ID7" on them and a "2" in a diamond.
 
I bought my 1960 BN7 in 1981. It had 93,000 miles on it. It was “burning” a lot of oil which was caused by a badly worn rocker shaft which allowed oil to be sprayed into the valve cover and drawn into the carb where it was burned. I replaced the shaft with an oversized shaft and had the pedestal bushings rebored. Totally fixed the blue smoke and nothing else was done to the engine. It maintains 40 lbs. at 3000 when hot and 20 at idle. If you can meet or exceed these, I’d leave it alone. Recently I removed the oil pan and observed a pristine camshaft. I cleaned the gunk out of the pan and the screen of the oil pump and have very clean engine oil. A compression check should reveal the condition of the rings and or valves
 
Healey nut, that is exactly what i thought.
i also figured i would measure the valve springs and see if they could use replacing.

the only thing i have seen so far is that one of the push rods was bent just a little. i rolled them all and they all looked good except one. Nothing in that piston to suggest any damage but i have marked that one rod.
 
Day 2 on the tear down. Mostly clean up and removing studs.

i do wonder about the timing chain. it looks good and the sprockets look great. but it seemed to have more slack than i thought it would. i measured the distance the tensioner was extended and it came to just under 7/16". the travel on the tensioner looks like it could go to 7/8" and still work fine. can anybody shed some light on if i should replace the chain? i am going to replace the tensioner which has some scores worn in it. you can see a pic below.
IMG_0262.jpg
tomorrow i plan to look at the main bearings and see what they look like. plus start some cleaning of parts. i also noticed the cylinders in this engine had liners in them. looking at the Moss catalog they show liners for later models but not a BT7. Maybe someone can shed some light on that as well.

oh, some other pics. always fun to look at.
IMG_0261.jpgDSCN0319.jpgDSCN0318.jpg

oh and i pulled the oil pan with the engine upright so i could look for anything, like shavings in the bottom. i found nothing there except some sludge. i also did not see any sign of anti-freeze in the oil.
 
There is an oil gallery running through the block, this can become porous with time as it passes through the water jacket, it is worth getting the repair kit and getting a shop to install it. Also it is worth getting your engine parts balanced before re installing. They will need the crankshaft and everything that goes on it from the clutch at the rear to the pulley and damper at the front including the woodruf keys and nuts etc. and the con rods. When I did my engine, I removed all the core plugs and spent a few hours cleaning as much rust and rubbish from inside the water jacket that I could get to with a long screwdriver, I also replaced my damper with a new one from Australia, a new oil pump and water pump, timing chain and tensioners, and cam bearings. The head had been refurbished some time before.

:cheers:

Bob
 
I'm no hexpert, but it appears to me your timing chain is a bit stretched, and the teeth in the cam gear are a bit sharp and have more of a '\_/' shape than a '|_|' shape (and the crank cog will likely be even more worn). Moss has a timing set with tensioner--although your tensioner may be OK--for under $200, and Tom's Import Toys will give you 15% off that. At the very least check timing at the correct valve lift (usually 0.050").
 
as always, thanks for all the help.
checked the main bearings today and they have to be replaced. three of the 4 looked like just wear a little in to the brass. but the thrid one was worse. So i spent the day pulling out the crank. of course with pulling the crank, i may as well pull everything out. i was hoping the engine had been redone at some point and this would be a quick run thru.... really, what was i thinking.. hahaha. Good thing is that i won't have to wonder now. So at this point i need to get it all out and start a list.
 
There is an oil gallery running through the block, this can become porous with time as it passes through the water jacket, it is worth getting the repair kit and getting a shop to install it.



Bob
have not read about thisn passage or the kit. can you give me more info on it?
Thanks
 
Block, head and crank went to the machine shop today. the block and head to be tanked and decked. the crank turned and balanced. new freeze plugs and having the valve seats done. decided to go ahead and put in new valves, springs and the umbrella seals. once the valves are out, we will check the guides. while at it, going to tank the vavle cover, the oil pan, and a few other parts. thinking it will be a few weeks with deer season about to begin. but no big hurry. i got plenty of other things to work on while waiting. anticipation.....
 
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