1950 8BA Rebuild Questions
- Thread starter kirkf
- Start date
GOSFAST
Well-known member
There's absolutely nothing wrong with the 4-ring pistons, we still have these on the shelf. Many customers still require them usually due to budget constraints!
I would add though if you are looking for any power gains at the same time as doing the rebuild then a 3-ring (moly/metric ring pack) piston is really the only way to go. It all comes down to the budget!
Thanks, Gary in N.Y.
P.S. I won't post numbers (mostly from dyno testing) but we consider the HP gains "substantial" from a basic 3 or 4 ring piston (with older type ring pack, 3/32" x 3/16") as opposed to Ross style piston with the "metric", "moly", L/W ring (1.5, 1.5, 3.0) packs! There's simply no comparison between the two types of pistons.
I would add though if you are looking for any power gains at the same time as doing the rebuild then a 3-ring (moly/metric ring pack) piston is really the only way to go. It all comes down to the budget!
Thanks, Gary in N.Y.
P.S. I won't post numbers (mostly from dyno testing) but we consider the HP gains "substantial" from a basic 3 or 4 ring piston (with older type ring pack, 3/32" x 3/16") as opposed to Ross style piston with the "metric", "moly", L/W ring (1.5, 1.5, 3.0) packs! There's simply no comparison between the two types of pistons.
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Interesting read! It seems he is putting 'O'-rings behind the compression rings at the top of the piston instead of at the bottom of the skirt. Did you notice at the very bottom of the article that this patent expired in 2005 due to "failure to pay the maintenance fee"? Must not have worked out.
There is also a reference to a 1927 patent for the same idea but using springs behind the rings instead of an 'O'-ring.
Other similar patents are listed; one by Ford Motor Company. Manufacturers are searching high and low for ways to both reduce emissions and increase fuel mileage so if these ring ideas get worked out, we may see them in the aftermarket.
V8COOPMAN
Well-known member
Yeah, and you could also buy a complete, brand-NEW Chevy for $1,759, as late as '59! DD
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kirkf
Senior Member
A 1950 mercury motor and transmission popped up on the local facebook classic cars for sale thread, so I ended up buying it. It was disassembled, but the owner chose to go a different route on his truck.
I'm hoping to have the block in my hands in the next couple weeks.
If the crank checks out ok from the machine shop I might substitute it in for my ford crank.
Kirk
I'm hoping to have the block in my hands in the next couple weeks.
If the crank checks out ok from the machine shop I might substitute it in for my ford crank.
Kirk
Byron Warwick
Senior Member
Are you considering going for the full flow oil pump, so you can use a modern spin on filter. Mine works well, and I got it from Speedway. I am running a '54 8BA Merc. Byron.
bssmnbll
Member
Fellows, are there no "poor retired Merc owners" out there that just do the old school "rings and bearings" thing any more? My car is stock, has 48000 original miles, has sat too long, and is showing a little oil on a couple of spark plugs. A compression test is in order, but it holds great oil pressure, no noise at all out of the engine, and quite frankly, I can't afford a $3-5000 rebuild on a Sunday driver. Any suggestions??
tubman
Well-known member
I'd say go ahead with what you're doing. You should do a compression test first to see if it's rings, valves, or both. Also, remember "Plastigage" is your friend.
I've got a couple that I'm doing that way now. One was a good runner except that it had stuck valves in two cylinders that wouldn't loosen up using the usual techniques. I'm just going to pull the valve assemblies on that one. The other ran great, had good oil pressure, but had a weird "rattling" sound when revved. When I pulled the pan, there was what appears to be a chunk of the thrust surface of the rear main about 1" long laying in the pan. When I get to that one I'll pull the rear main cap and see what's up. I discussed this with my machinist and he says it was probably a defective bearing or an assembly error.
When I was in high school and college, I did a bunch of engines this way. Sears had all the parts you needed dirt cheap and my mom would let me use her Sears card. For one engine, I scored a set of 7 almost new pistons from the local machine shop cheap (something went wrong with the eighth, I guess). An afternoon in the "piston pile" at Carmichel's Auto Parts produced the eighth. That engine was still running good 3 owners later.
I've got a couple that I'm doing that way now. One was a good runner except that it had stuck valves in two cylinders that wouldn't loosen up using the usual techniques. I'm just going to pull the valve assemblies on that one. The other ran great, had good oil pressure, but had a weird "rattling" sound when revved. When I pulled the pan, there was what appears to be a chunk of the thrust surface of the rear main about 1" long laying in the pan. When I get to that one I'll pull the rear main cap and see what's up. I discussed this with my machinist and he says it was probably a defective bearing or an assembly error.
When I was in high school and college, I did a bunch of engines this way. Sears had all the parts you needed dirt cheap and my mom would let me use her Sears card. For one engine, I scored a set of 7 almost new pistons from the local machine shop cheap (something went wrong with the eighth, I guess). An afternoon in the "piston pile" at Carmichel's Auto Parts produced the eighth. That engine was still running good 3 owners later.
Frank Miller
Well-known member
Not sure where you are located so that does not help answer your question. Disassemble the motor and clean everything up and inspect it. The bearing are relatively cheap so I would replace those as well as lightly honing the cylinders and replacing the rings. Also inspect the valves and at the very least lap them before assembling. This will not be a new motor but it will be better than what you started with.
