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MGB Drew's going to build an engine this winter

drooartz

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So last winter I was planning on tearing down the spare MGB engine (18V) that I got for free from a friend. Didn't make it all that far, been sitting on my engine stand ever since.

https://www.britishcarforum.com/bcf...Follow-along-as-Drew-tears-down-an-MGB-engine!

Well, I've decided to try my hand at building an engine for myself this winter. Had a nice chat with Hap today (thanks!) so I'm going to dive in again and get this engine torn down so I can see what I have to work with. I've also got a line on a spare 18GB block of unknown condition and completeness. Hopefully between the two and what I can scrounge locally I'll have enough of the crucial bits to pull this off.

The plan is to build a mildly warmed up engine, nothing extreme, but no corners cut either. I still want to do a supercharged engine but the funds just aren't around right now. This way I'll have a nice solid engine for the next few years while I save up the resources for something more special (and that new Bugeye's got some needs as well).

I've never rebuilt an engine before, so this will be a fun learning experience. I'm going to revive my old tear-down thread and document the whole process. Going to get cold soon here, so it'll give me something to do inside. :grin:
 
One of the most rewarding deeds possible! I've only built a few - VW's to MGB's to Rover V8 - but have enjoyed each one. Especially that first startup.

Have fun!
Mickey
 
Drew, that 18GB block would be the one to use as a "base" if it hasn't been hogged out badly. Mic the bore to see if it has any meat left! That'd be a "period correct" mill for the car, make the 18V the "hot" one.

The 18GB here has a Crane cam, 40MM Weber side draught and 80K miles with no issues. Tough as nails!
 
Going to use whichever block is better for the build this winter. I'll eventually rebuild the engine that's in the car (18GG) as the performance one -- it's the original engine for the car, and long term I want to leave it in there.
 
Great topic! :smile: I know "supercharger funds" aren't handy right now, totally appreciate that one! My logic says the only internal parts specific to supercharging are pistons and cam. Is it possible to build the engine with supercharger pistons and cam and run it normally aspirated? Then when funds for the rest are available, you are already half way there and have an engine that has some hours on it - a known entity as it were. I probably am off base with my logic and I know wiser minds will shed the appropriate light on the matter. :smile:
 
Great topic! :smile: I know "supercharger funds" aren't handy right now, totally appreciate that one! My logic says the only internal parts specific to supercharging are pistons and cam. Is it possible to build the engine with supercharger pistons and cam and run it normally aspirated? Then when funds for the rest are available, you are already half way there and have an engine that has some hours on it - a known entity as it were. I probably am off base with my logic and I know wiser minds will shed the appropriate light on the matter. :smile:

I had a supercharger fund going pretty well, then I bought a Bugeye instead and that was that... :grin:

The Moss supercharger setup is designed for a stock B engine, so if you went that way you could always bolt on later. If I do ever go down that route, I'll do more supercharger-specific things to it'll be a pretty purpose built motor. Many years down the road, though, so just doing a nice warm street motor is the ticket for now. This build will be value-for-money, should still be plenty nice for the car's purpose. I'll do something wilder with the Bugeye.
 
My home for the winter

So I've set up my mini-shop for the fall and winter. Though I've got a nice new shop built out back, it still lacks insulation and heat so I'm setting up in the attached garage for the build. Going to build a simple bench/table along the side wall so I'll have some work space and I'll get to the disassembly.

Not the ideal space, but it's enough room and the attached garage is insulated and heatable.

workshop.jpg
 
Looks good from here - a lot brighter and roomier than what I have to work with.
 
Looks good from here - a lot brighter and roomier than what I have to work with.

It's a functional space, but I really wish I could be working out in my new little shop. The shop is not huge (12'x20') but it's dedicated space with plenty of power. It's just not done yet, and with no insulation or heat it will shortly be unusable.

I will be building a little bench where those green plastic tables are now. It'll work.

Gives me an opportunity to pick up a few new tools as well, as my main set lives out in the shop. Never a bad thing to pick up a few new tools. :grin:
 
So last winter I was planning on tearing down the spare MGB engine (18V) that I got for free from a friend. Didn't make it all that far, been sitting on my engine stand ever since.

You and me both!

I have a 1500 bored out to something like 1648 (+0.060" 1600 pistons) that came as spare parts with my car. I got started on rebuilding the head last year, but got bogged down when I was at the "porting" process. The block is on the engine stand. All basic parts are there. I need to decide if I want a more aggressive cam, and need to double check the oil pump as the old bearings suggest oil starvation, but otherwise, I hope to get that rebuilt pretty quickly (wishful thinking?) (although today I was looking at the JE Piston site and thinking flat topped pistons.)

Then I have the orphan 1600 engine that I lent out last year in an effort to get the #76 Honey Bee on track after it blew its engine. Just returned a week or so ago. Turns freely, but no compression. Guessing valve recession on #3. So that will at least get torn down to look at.

And then there is the engine in the car. Built by the prior owner with about 8 race seasons. Before I learned to drive, my "race seasons" were pretty mild on the engine; but this year, I've been hard on the car and the engine is due for a refresh.

I brought all of my rebuild articles and research in to work today and will make a notebook to use during the rebuild processes - will use one section for my rebuild notes - sort of like a lab notebook from physics class.

So good luck to you Drew, and good luck to me.
 
For us autogeeks, building an engine is probably the most educational thing one can do. If nothing else, it will really impress on you the necessity for clean oil and good lubrication.
 
So good luck to you Drew, and good luck to me.

Hope your builds go well, and more importantly, I hope they go!

I'm really looking forward to the learning process. Never done an engine before, and I figure the best way to learn is to dive in and do it.
 
I did an exploratory search of the top end of the 1600 orphan engine. Supposedly, it had no compression in #3. From the outside, there seemed to be some defect in the gasket opposite #3, but that turned out to be a small chip in the block. It didn't extend but about 1/16th inch deep and couldn't have amounted to the problem.

Rather, the head might have been loose. (I hope not warped!) Several bolts were loose and there was a lot of discoloration between the gasket and the block.

The tops of the pistons cleaned up nicely with kerosene and were standard bore flat top pistons. The cylinder bores did not look scored and held the kerosene, so I assume the rings are OK. At the top of the pistons, there seemed to be one spot on each bore where the pistons "wore in". As if the pistons were not running straight up and down. Indeed, as I rotated the engine, there seemed to be one spot where it became more difficult to spin the engine. That deserves further assessment.

The head looked pretty good. I'm not sure I actually know what valve recession looks like, but I don't think I had it. The rockers looked good and the shaft did not seem to have any wear on a cursory examination.

I put everything back together finger tight until I can bag stuff up and keep it all sorted. I have to look for a second engine stand so that I can work on the two engines at once.

Cheers
 
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