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BMC Replacement engine

Posted: Mon Jun 19, 2023 12:27 pm
by robertscottcostello
Greetings to all.

I am the new owner of TC7556. I have a tag on the XPAG showing it to be a replacement engine from BMC.

BMC
REPLACEMENT ENGINE
BORE SIZE .040"
CRANK SIZE R2
PART NO MG8624R

Any insights?

thanks,

Rob C

Re: BMC Replacement engine

Posted: Mon Jun 19, 2023 1:38 pm
by Steve Simmons
Congratulations! We love photos (hint hint).

What you have is a factory rebuilt engine which was likely dealer installed at some point. The bore size is easy, 40 thou over standard. I believe R2 means the crank was "reground -0.020". I assume the part number is for a complete 1250 engine and the 'r' means rebuilt or reconditioned.

Re: BMC Replacement engine

Posted: Mon Jun 19, 2023 2:23 pm
by antijam
R2 refers to the first regrind of the crank to minus 0.020", not 0.002". The next standard regrind was R4, that is minus 0.040"

That plate was certainly fitted many years ago and you'd be unwise to assume that it necessarily relates to the present condition of the engine.

Re: BMC Replacement engine

Posted: Mon Jun 19, 2023 2:33 pm
by Steve Simmons
Whoops, I transposed my last two numbers! I'll edit that so no one is confused.

Re: BMC Replacement engine

Posted: Tue Jun 20, 2023 11:08 am
by robertscottcostello
Thanks. Pics coming soon!

Re: BMC Replacement engine

Posted: Tue Jun 20, 2023 11:12 am
by robertscottcostello
antijam wrote:
Mon Jun 19, 2023 2:23 pm
R2 refers to the first regrind of the crank to minus 0.020", not 0.002". The next standard regrind was R4, that is minus 0.040"

That plate was certainly fitted many years ago and you'd be unwise to assume that it necessarily relates to the present condition of the engine.
Good advice. With any luck I should have some good life before I need to do any motor work.

Re: BMC Replacement engine

Posted: Tue Jun 20, 2023 11:15 am
by robertscottcostello
I'm thinking of creating a PDF for newbies like me.

Fluids - motor, differential, transmission, coolant
Dash - everything

Re: BMC Replacement engine

Posted: Tue Jun 20, 2023 11:30 am
by Steve Simmons
You'll get lots of differing opinions on fluids and other sundries. I've changed my own mind over the years as I've experimented and found better (in my opinion) products, My current choices are:

Engine: Valvoline VR1 20W-50
Gearbox: Redline 75W-140 NS
Rear Axle: Royal Purple 85W-140 or Redline 80W-140
Steering Box: Redline Heavy Shockproof (In both BC and Datsun boxes)
Cooling: Prestone green, 20% mix (no freezing danger here)
Brakes: Any name brand DOT4. I've also used DOT5 with no issues.

Re: BMC Replacement engine

Posted: Tue Jun 20, 2023 5:59 pm
by robertscottcostello
Thanks Steve. I don’t see a chart for amounts in Sherrell. Roughly how much should I be expecting to purchase?

Re: BMC Replacement engine

Posted: Tue Jun 20, 2023 10:51 pm
by Duncan M
The gearbox and differential will each take almost a regular US quart. You should have a little left over.

I tried standard 140W (GL4) in the gearbox and found that when filled to the proper level it foamed like crazy. Now I use the Redline NS in the same multi-weight (75W-140 NS) as Steve suggested. Do not use a lighter weight oil in the gearbox.

(GL4) 140W gear oil in the BC steering box works fine. There should be no need to use anything thicker.

Always run clean 20W-50 in the engine. Sludge seems to form very easily in these engines, even with advanced filtration. 2000 miles is pushing it for me. I prefer to dump it every 1,000 miles to avoid sludge. Sludge will clog the pickup screen for the oil pump-- in the sump...

Re: BMC Replacement engine

Posted: Wed Jun 21, 2023 6:58 am
by Steve Simmons
Interesting, I've never seen a sludge issue even on TCs that don't get driven much. I wonder if it's the higher humidity up there.

There may also be a slight variation in dipsticks or top cover castings because the last gearbox I filled took just over a quart. I've seen others take just under. I seem to recall the engine is supposed to take 5 quarts but plan on 6. Takes about 2.5 pints for the rear end if I recall correctly.

Re: BMC Replacement engine

Posted: Thu Jun 22, 2023 5:52 am
by robertscottcostello
Thanks Steve and Duncan. Here's what I have for a shopping list +-

Engine oil 6 qts
Gearbox 2 qts
Differential 3 pts
Steering box 1 pt
Coolant 1 gal
Brakes 1 qt
Scotch 750ml

Next is the oil filter. Looks like I have a spin-on, but the Lucas filter shows no markings. Framm shows a spin-on almost five inches tall. Existing is three inches. I was thinking of using a PH3675 in my cabinet, but it appears the thread might be different. https://www.framfilters.ca/parts-search/PH3600

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Re: BMC Replacement engine

Posted: Thu Jun 22, 2023 6:32 am
by antijam
I have a spin-on conversion using a WIX WL7074. This is 3¼" tall and works fine.
P1290102.JPG

Re: BMC Replacement engine

Posted: Thu Jun 22, 2023 6:56 am
by Steve Simmons
I have a Phil Marino spin-on adapter, which is the same dimensions as the Roger F and Bob G versions. I use K&N HP-2009 filters on them. Anything in that size range should be fine.

Re: BMC Replacement engine

Posted: Fri Jun 23, 2023 6:02 am
by robertscottcostello
Thanks. Oil is changed. Gearbox and diff are next.

Re: BMC Replacement engine

Posted: Fri Jun 23, 2023 8:48 am
by Duncan M
Of the 3 plugs on the differential (drain, fill level, and filler plug on top) you want to be sure the vent in the filler plug is clear/open. If you can get a whole quart in there without overflowing at the fill level (open) plug, I will be surprised. Let us know.
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Re: BMC Replacement engine

Posted: Sun Jun 25, 2023 4:33 am
by Ray White
Incidentally, you may or may not be aware that in England a "vintage" car is one that was built before 1931.

Presumably this is not the case in America.?

:thumbs:

Re: BMC Replacement engine

Posted: Sun Jun 25, 2023 1:15 pm
by Duncan M
Ray, does the term "vintage" and the 1931 date determine some sort of tax or safety certificate exemption in UK? If so, there is nothing comparable in the US.

AFAIK, in most or all US States, if you have a car that was originally sold with (for example) no turn signals or running lights, carbide headlamps and no windshield wipers, it would be legal to drive on the road (anywhere in the US) as long as it is registered/licensed in a State.

Re: BMC Replacement engine

Posted: Sun Jun 25, 2023 4:33 pm
by Ray White
Duncan M wrote:
Sun Jun 25, 2023 1:15 pm
Ray, does the term "vintage" and the 1931 date determine some sort of tax or safety certificate exemption in UK? If so, there is nothing comparable in the US.

AFAIK, in most or all US States, if you have a car that was originally sold with (for example) no turn signals or running lights, carbide headlamps and no windshield wipers, it would be legal to drive on the road (anywhere in the US) as long as it is registered/licensed in a State.
Hello Duncan. The term "vintage car" as defined in the Oxford English Dictionary relates to cars that were built from 1919 to 1930 inclusive. It does not relate to any specific feature of cars from the period or have any legal status. It is merely a dating tool and nothing more. It was first coined in England by the VSCC (Vintage Sports Car Club) in 1934 as a cut off date; after which cars would not be eligible for their events. This rule was later amended to include certain cars built before the War that fell into a category called "post Vintage thoroughbred" .

Cars built before 1919 are known as Veterans with a relevant sub section that caters for "Edwardians."
That is; cars built during the reign of King Edward V11 ( 1901 - 1910).

There are certain absurdities with having a cut off date of December 31st 1930. For example, I have an Austin Swallow Saloon that was built in September 1930 and is thus a "Vintage" car... but someone with a virtually identical car built in January 1931 would not be correct in using the term.

Having said that, a vintage period car is not necessarily worth any more than a non vintage one; the term is, as I said , merely a dating tool and nothing more.

Re: BMC Replacement engine

Posted: Tue Jun 27, 2023 6:53 am
by robertscottcostello
Duncan M wrote:
Fri Jun 23, 2023 8:48 am
Of the 3 plugs on the differential (drain, fill level, and filler plug on top) you want to be sure the vent in the filler plug is clear/open. If you can get a whole quart in there without overflowing at the fill level (open) plug, I will be surprised. Let us know.
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I was hoping to fill from the underside (I have a four post lift) as I don't want to disturb the vinyl the way they have it installed. If push comes to shove, I will be pulling a few staples.
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