By Tom Ware, with thanks to Mike Meindorfer
Originally published in the Austin-Healey Magazine, March 1988
This project started out as a front timing cover seal, timing chain, and tensioner replacement. My feeling was that since the seal was leaking and I would have to replace it, I might as well replace the timing chain and tensioner on my 100,000+ mile engine. I ended up replacing the camshaft, lifters, oil pump, oil pressure line, water pump and painting the engine as well as porcelainizing the exhaust manifolds (I know it isn't “concours”) and rebuilding the carburetors. My particular engine had excellent compression, redone rocker shaft assembly and valve job about 6,000 miles previously. The best part of this project is that the engine does not have to come out of the car.
This is not a project to be attempted in a weekend by the average Healey owner. If your luck is like mine, something will leak or not fit, have to be redone or you will have the wrong or missing parts. Hopefully, no parts “left over”.
I already had a conversion gasket set which gives all the gaskets from the head down. I also ordered a timing chain, tensioner, keys, washers and the seal for the timing cover. I didn't know at the time how far I would be going. Had I known, of course I would have ordered the rest of the parts at the same time. It's a good idea to order everything you think you will need at the same time to prevent delays. You might save on shipping, too.
The tools you will need are really only basic tools that most Healey owners should already have. The only unusual ones are the 1-5/16 inch socket and 1-11/16 inch socket for removing the camshaft nut and crankshaft nut, respectively. To my knowledge, these only come in 1/2 inch drive. You should also have a factory service manual handy. You may wish to steam clean the engine area to remove grease and grime before you start.
Prepare to raise the car about 3 to 4 inches using ramps. I fashioned a pair of ramps of two pieces of 2x6 lumber nailed together and then angle cut one end so the car could be driven on. Be sure the nails don't extend! The finished ramps are about 18 inches long and about 3-1/2 inches high. You will be raising the engine with your floor jack so you don't want the ramps to be much higher. Because you will be raising the engine, I don't recommend using jack stands alone. Be certain your parking brake works and that you set it once the car is upon the ramps. Also, disconnect the battery or switch it off.
Next, drain the radiator engine, block and heater lines. Drain engine oil. Remove the radiator, fan, belt and generator. I suggest painting as many engine parts as possible off the car. You'll get better coverage and surface preparation. Continue on and remove the carburetors and manifolds. At this point, you have good access to the engine for cleaning. Stuff rags or paper towels in the ports and cover the distributor and brake fluid reservoir. "Gunk" the engine thoroughly if steam cleaning didn't get it all. I used a stiff bristled parts cleaning brush to remove the more stubborn deposits. Rinse off and do it again Until it's clean in there!
Once the engine is dry remove the oil pan Place a block of wood (4x4 should do) about 11 inches long on the floor jack pad and move it under the front of the engine. Now, withdraw the eight bolts holding the motor mounts to the frame. Next, raise the engine with the jack so you can get the 1-11/16 inch socket on the crank nut. For future ease of assembly and starting, set the engine at TDC on the crank pulley now. Place the transmission in gear and block the crank with another piece of wood. (Parking brake is on.) Knock back the tab washer and remove the crank nut. It should be difficult to remove. I suggest a breaker bar and your wheel hammer. You may need to place more wood blocks under the motor mounts to prevent excess rocking of the engine.
You still can't remove the vibration damper/pulley so you will have to raise the engine some more. Try not to raise it into the firewall, like I did. Remove the vibration damper/pulley with a puller, by hand or by levering it off with large screwdrivers, but be careful not to bend anything. It may come off suddenly so be careful. You will find that it is the damper that fits inside the seal, not the crank. Once the pulley is off, inspect that portion of the pulley which fits inside the seal for ridges. If ridges are present, the replacement seal may not completely stop the leak. If you can find one, it would be a good idea to replace the pulley. Remove the front timing cover. Remove the damper key. Knock back the cam gear washer and remove the cam nut with the 1-5/16 inch socket. Remove the chain tensioner.
Remove the gears and chain as a unit. Note the bright links line up with the dots on the gears. Remove their keys. Note the shims behind the crank gear. They are there to align the chain on the gears. I removed the front engine plate and motor mounts from the block next for better painting and because it was about this time that I was coerced, cajoled and coaxed into going "all the way". The camshaft was going to be reground.
In order to get the cam out, the distributor and drive gear have to come out. Note the "twenty-to-two" position of the drive gear. It has to go back in that way or you'll be up 'til midnight trying to figure out where you went wrong - one tooth off and the engine won't start. Remove the oil pump and drive gear spindle. Remove the rocker cover, shaft and pushrods, keeping the pushrods in order. Remove the tappet covers. Remove the tappets. Although you will have these resurfaced, try to mark them so they go back in the same bores. You will have to remove the grille because the cam is longer than you might think. Now, carefully, with a twisting motion, remove the camshaft. Don't let it damage the cam bearings. It is also heavier than you might think. Sit back and have a beer or two while you inspect the cam and lifters for unusual wear.
Now you can take parts like the oil pan, timing cover, etc. out to be stripped for painting. I talked with a Healey friend who recommended Elgin's Machine Shop as a quality shop to regrind the cam and lifters. I spoke with Gordon Meacham there who is a Pacific Centre member and was at Snowmass in 1982. It is important to locate someone like Gordon who "speaks Healey" and knows what he's doing. He can suggest particular grinds for the state of tune of your engine. He reground my cam and lifters (always do both) and hardness tested the lifters, marking each one. This is important as the face of each lifter is hardened but not all the way through, so heavily pitted lifters or excessively worn lifters may have to be replaced. (Figures 1 and 2) My bill for Gordon's work was a little over $100. A bargain considering that I've seen new camshafts for as much as $300 and new lifters at about nine dollars each.
Putting the engine back together is the same as taking it apart, only in reverse procedure. A few hints are in order, though. Seal the gasket surfaces with a light coating of Silastic or Edelbrock RTV silicone sealer before assembly. Be sure to use assembly lube on cam lobes and lifter faces. Basically, follow the cam grinder's instructions, but standard procedure would indicate use of a straight weight motor oil and new filter for the initial start up. When you start the engine, be prepared to run it at 1,500+ RPM for about half an hour to seat the new cam grind to the lifters, then immediately change oil and filter again. You can go back to using whatever oil you're comfortable with after this.
Installing the new seal in the old cover is not difficult but does require care. It’s interesting to note that the factory manual says replace cover and seal as a unit. They apparently were available already installed together. Since this is no longer available to my knowledge, use a piece of 2x4 and trim it to fit roughly inside the length of the cover. Place the cover over the wood on a flat surface. Put the seal in it's place and use the second piece of wood as a drift. Use a hammer to drift the seal home. Your goal is to have the seal in straight and not deform the cover. The factory also had a special tool for this so the cover didn’t even have to come off to replace the seal.
Once you've reinstalled the cam, tab washer (don't forget to bend this over), nut front plate, thrust plate, new keys, gears, chain tensioner and oil thrower, you’re ready to reinstall the front cover with new seal. By the way, be sure to use new keys as worn keys are often the source of engine noise as the damper/pulley or gears rock back and forth. Coat the gasket and reinstall the cover, but don’t tighten the bolts yet. Also, note there are two sizes of bolt and oval washer here. Place the new damper key in the crank and slide home the damper. You left the cover a little loose so the seal would center itself on the damper Now tighten the cover bolts and reinstall the crank nut and washer. Bend the tab washer over the nut once the nut is tight - very tight.
Dip the lifters in oil and assembly lube the faces and reinstall in their respective bores. Reinstall pushrods and rocker shaft and adjust valve clearances. Turn the engine over manually to keep wear at a minimum. Be sure it's out of gear but that the brake is still on!
Paint the tappet covers, oil pan, valve cover, etc. and reinstall. Newspaper and masking tape are needed next. Carefully mask off the entire engine bay, shroud and hood (bonnet?). Moss Motors has a good “Healey green” engine paint in spray cans, even though it’s a bit pricey at $10.95. I needed three cans and had some left over so you might be able to get by on two cans. I’m told that Bill Hirsch has a good Healey green as well, only in quarts. One quart should do the job. He is a regular advertiser in Hemmings Motor News. Spray the engine, let it sit for a bit, then remove the paper and tape and leave it alone overnight.
Reinstall the distributor making sure the drive gear goes in the same way it came out (the twenty-to-two position). Hook up the wiring, belts, etc. and install the new oil pressure line. Replace the motor mounts and bolt up to the frame. Put the floor jack away. Put the manifolds and carbs back as well as the radiator, fan, hoses, etc. Fill the radiator. Don't forget to close all the petcocks. fill the engine with high quality 30-weight oil. Don’t cheap out at this stage of the game. Be sure you have enough gas in the tank for the half hour break in. A quarter tank full is plenty. Look over everything to be sure you have it all hooked back up and there are no “extra parts”.
Have a friend handy to watch for fluid leaks or anything unusual such as smoke! Switch on the battery and “Gentlemen, start your engines!" Keep the engine running at 1500 RPM or more (but not less) for the next half an hour. Vary the engine speed during this time. After that, shutdown the engine, drain off the oil (it will be dark due to the assembly lube) and replace the filter. Fill up again with whatever weight oil you’re happy with, and enjoy the fruits of your labors! After the first 500miles or so, go back and re-torque the pan and front cover.
As a postscript, I can tell you that the engine now has more power, runs quieter and has the elusive 55 lbs. oil pressure when hot I believe that the oil pump replacement did more for renewed oil pressure than the rocker shaft rebuild and strongly recommend this to you.
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