The 100-Six Forum

My engine has been chemically cleaned, pressure tested and the surfaces have been skimmed and polished. The bores were reground to +060".
I bought the car as a project in 1988, but have only just started on it.
I intend to do the head first and I am aware of the need for pristine cleanliness, but if anyone out there has rebuilt this engine, please get in touch.
Roger.

It's the most important part of the car I would let a professional do it just my opinion good luck

It's a great opportunity to learn, that's for sure. When I bought an MG Midget 7 years ago, I was not especially mechanically inclined, and only had a small set of tools to my name. After that car broke 2000 times, I now have no second thoughts about getting someone else to fix it, I can learn how to do anything myself (but I scratch my head every time a Honda Civic needs a repair). An engine rebuild is a tough job, and does need to be done in a clean environment with the right tools, but can be done by the knowledgeable owner (these cars, and many classic vehicles, were practically designed to be repairable by the owner, not dealer-only like many modern cars)

Not knowing your mechanical skills, My only recommendations would be to have a friend who has rebuilt pushrod engines before lend a hand. There is nothing to my knowledge that makes your engine any different (aside from it's rarity) from any other inline engine of the day.

Keep everything numbered and organized, and put parts back in where they came from. You will probably need to clean up the valves, possibly a lapping is all that is necessary. Measure the unsprung height of the valve springs and compare to required specs, replace ALL springs if one spring is squashed or even looks funny, small price to pay to not have misfire at high or low RPM.

If you're just doing the head, do it, it's easy once you learn the basics. Buy the best headgasket you can afford, and torque the bolts down as specified by any manual (a little at a time, in a spiral/star pattern)

Installing the pistons and such is easy too, provided you have the correct tools, +.060 parts (like pistons and matching rings). Make sure to study the manual and take notes before diving in. Watch several hours of YouTube videos to get a visual lesson, there are many good sources who make youtube videos about rebuilding engines like yours.

Roger,
I have rebuilt my engine. Although I had all the machining done by a specialist all the assembly work I did myself.
One thing I do highly recommend you get done is get you engine balanced.

If you have mechanical knowledge assemble is straight forward, three key things. Take your time, cleanliness and recheck items before assembling ( measurements and tolerance )

aa

Thanks to those who have already replied.All the machining, skimming, polishing and testing has been done professionally, and it is more a case of putting the components back together.
The reply from aa in Melbourne, Australia was interesting as you've done it yourself.
Although we are 'poms', we are downunder in March/April 2015, so maybe we could meet for a chat??
If so, we can get in touch?
Roger Chauffeur

One quick point, Go get yourself some plastic gauge and see what your finished machined clearances are first
(unless your accurate with a measuring device)
The idea with the plastic gauge is that you put a small amount onto lets say a crank shaft or rod journal (DRY) then assemble the corresponding connecting rod or cap with the assembly and torque down to the spec.......Then remove the cap or rod and see how far the plastic gauge has crushed down too..... (on the plastic gauge box, it will tell you what clearance you have by how much the plastic gauge has squished down... (in your service manual, it will tell you what the spec is 0.001-0.004" and if your within it your good, go too the next rod and measure that one)
***It is important that whatever your measuring, it;s the correct parts that go together...***
DONT MIX PARTS UP
You should be able to measure all the rod big end bearings and crankshaft main bearings this way..
You should measure everything, don't rely on the machinist (everyone makes mistakes)
Get yourself the service manual for the vehicle,cause your going to need it (besides the information in reassembly it has tons of specs)
Cheers,
Ted

Also pay particular attention to the piston rings. Check the piston ring gap in the bore (explained in the workshop manual), and the positioning of the piston ring slots, which is not explained.

Theres so much to learn but don't be put off, get the service manual..
You can always ask questions, there are many things to do and get through but take it slow and steady and you'll get there....
I have noticed the Austin Healey engines utilize offset connecting rods...... Make sure you reassemble correctly or read the service manual in proper reassembly..
This isn't a complicated engine, just ask questions if your not sure...
Ted

I have rebuilt a bj8 and bn6 engine and helped on quite a few other ones. I have the machine work done then put it together myself. I take my time and constantly doublecheck everything I do. I always have the manual there and read the section on the part I am working on even if I have done it many times.

Hi Roger

Take the time to look on (You Tube) Matthew Randall in Australia is nearing the finish of his 100/6 and has videos of most everything he has done from the Chassis, Gearbox, Overdrive, Welding panels and paint prep great workmanship and very well presented rebuild. Data that I will be using as my refference as I bought this project in five trailer loads, Its a Healey 3000 1962 BT7 Resurection / Restoration from the mass of components I purchased.
As I have no strip down notes and pictures to check back on I was looking for as much information as possible to assist in the task as I plan to make new panels in Aluminium and steel to replace the badly damaged parts and Matthew's videos are spot on..

Ron

Hello Roger,
Rebuilding the engine is no real problem. The Austin company issued very good shop manuals which detail all the exact needs.I have done my BJ8 engine three times using the shop manual( I am a chemist by training). I did my first engine with no help when I was seventeen using an Austin Manual. I suggest you take pictures with a digital camera as you disassemble the engine so you can refer to them as you put it back together. Get a good ring compressor as you will need it so the rings are tight as you ease them back into the bore so you don't brake them. Torque every nut and bolts three times. I'd replace the head studs with ARP studs Nuts and washers, you can buy them from Denis Welsh. The bottom end studs seem to last with no problems. Grease every part you put back with a cam grease containing ZDDP
If you need pictures send me your E-mail address(my E-mail is GeoSClark@aol.com) and I will send you the pictures we took as we re-assembled our Bj8 engine. We are just coming to the end of a three year complete remanufacture of the car starting with a new frame. We did all the work ourselves save for the frame and the paint.
Regards
George

Hi Ron,

Matthew's youtube series is very useful, and has given me some encouragement.

As soon as the UK gets back to work again on Monday, i can start to order the parts needed to start assembling the head.

Thanks for putting me on to him,

Best wishes from cold and wet England,
Roger.

Hi Roger,
Get yourself a factory workshop manual, read everything twice and don't cut any corners at the machine shop.
You may want to pick up a copy of "Healeys and Austin-Healeys" by Peter Browning and Les Needham. There is a chapter on tuning
that includes all the modifications the factory made to the rally cars, that's what I used as my guidelines.
I rebuilt my engine twice in the 42 years that I've owned the car and the only problem I ever had was a loose front harmonic balancer.
You can do this yourself but find a good machine shop for cylinder head work like valve guides and seats. You may want to line bore the
the main bearings caps and balance all the reciprocating parts. The machine shop should be able to do this for you.
I invested in COSWORTH Racing pistons .040 oversized and the engine has been running great since the last rebuild in 2000.
I've attached a list of modifications that I've made to my car which may give you some guidelines.

Write anytime if you have questions.
My e-mail is: carbonedesign@twcny.rr.com

Good luck,
Peter Carbone

I agree with above. An engine rebuild is not for the hobbyist.

Roger - I'll be re-reading these comments when its time for me to do the same - rebuild. Likely next year after this summer's driving. My only comment is ditto to taking images and using them as a catalog for reversing all actions you took when taking the engine apart. It's worked incredibly well for me doing a make-over on my car. Granted the engine is not like other aspects of the car - given everything is held together with nuts and bolts. There is no mystery when bits are removed carefully with patience. Good luck, enjoy the experience.