WillieB's 1275 Engine Rebuild

[cstudep]

That timing cover looks huge, from that perspective at least.....but oh so pretty.

[MPlayle]

I have not seen spacers like that used on a thermostat housing before.  Also, normally there are shorter studs so that only a washer is needed under each nut.

I note the spacers are also different heights.

Edit: Is there going to be a flywheel housing breather?  That fancy belt drive housing does not have a breather on it and a 1275 needs at least one good breather, if not two.

[MiniDave]

The spacers are so the radiator bracket will line up. I think he said this was a metro engine originally.

Me, I'd go with the original short studs and a different bracket.  77.gif

I'll have to check to see if there's one on the clutch housing.....but you're right, it definitely needs one.

[cstudep]

Is the mechanical fuel pump just your test stand setup or is that what he is running on the motor as well? Always the option to put one there as well if running an electric pump.

[MiniDave]

Yep, that's what he runs so that's what it has. Yes, I've seen kits to put a fitting in the fuel pump hole for a crankcase vent......

I run an old electric pump on the test stand.

[MiniDave]

Getting closer.....

The burette and plate came in so today I'll lift the head off and CC the chambers, then we'll know what to do from there. We're thinking that I will go ahead and grind out some metal and bring the compression down that way rather than wait for up to two months for a special head gasket if the results are still where we think they are.

As you can see, the clutch housing does have a breather, but I agree more is better. If there's one off the valve cover too that would help.

[cstudep]

Looking good 4.gif

Isn't the oil fill cap vented? Obviously it's not a huge vent so may not help much and maybe they are not all vented, but I know the one on my car has a small hole in the cap and the bottom side of the cap is filled with a steel wool like substance to help filter the oil out of the air similar to the large breathers.

[MiniDave]

This is just his "shipping" valve cover, I don't know what he will be using on the engine. these plastic caps may be vented, but they don't have any material inside them.....

It shouldn't have any blow by to speak of, so the venting need should be minimal.

[MiniDave]

After some discussion, we decided that I would go ahead and resize the combustion chambers to get the compression ratio more in line....our calculations indicate we need to go from the current approx 21.5CC to 24 to get compression down from 11-1 to 10.3-1.

I copied a pic out of Vizard's book to get an idea of the best place to remove metal, and decided if I could get enough off from the exhaust valve area that would work the best (Areas marked C and D in the pic) . In these pics, the green area is inside the fire ring, so at the edges I did not want to remove any metal if I could help it, just enough to blend in the new area (areas marked XXXXX).

I marked a small area off in red and took my burr in my die grinder to it - going really slow and carefully so it would blend at the bottom and not leave any sharp edges that could evolve into hot spots that could cause detonation or trap carbon. You don't want a polished surface, but rather a slightly imperfect one as smooth surfaces cause the fuel droplets to condense and you don't get as good and complete of a burn. After the first go around I had only gained about 1 cc, so I marked off a larger area and went at it again. After blending and polishing I rechecked it and had my 24 cc. I did the second chamber in one go and measured it and bingo - right on the money!

I had to cut away and take the bride to dinner and do some other honey do's so I won't get back to it till tomorrow.

Die grinders use a lot of air - especially my 35 year old and well used one - so it was nice to be able to have the new air compressor which not only could keep up but would shut off for quite a bit even when I was going at it pretty long and hard....not to mention the grindier stayed at full speed unlike with my old compressor where I'd get about 30 sec of full speed then it would begin to slow down.....then I'd have to stop and wait 5 min or so for it to catch back up.

[MiniDave]

And the last pic showing the difference in shape once they were done....no it's not your eyes, one side is shinier than the other! I took a scotch brite pad to the one side to make sure it was perfectly clean and to give it just enough tooth to hold the gasket.

[Jimini II]

Nice work Dave I am sure Brad will be happy with the results.

Regarding the air pressure on your air compressor I found by adding a large second tank with a gauge and two outlets my compressor now keeps up with any job I need to do. I also have a manual shut off if I don't need that much air volume.

[MiniDave]

I barely have room in my tiny shop for this one!  ::)

In fact, I've been thinking about relocating it to the basement. It pretty much only runs when I'm doing something air intensive like using this grinder, otherwise it fills up and can sit for days if all I'm doing is using an air gun occasionally. The only downside for that would be if it's noisy enough to be disturbing upstairs......

[Jimini II]

I really dont use mine that much anymore.
With the battery powered tools available now i seem to only use the air compressor when using bodywork tools or airing up tires lately.

[MiniDave]

I guess it depends on what I'm doing, if I'm tearing down an engine or a suspension the air tools are really helpful. Putting things back together I don't use them as much so I can judge the torque I'm putting on the fasteners. And of course, I use the heck out of my air blower gun to dry parts off or clean them. At some point I'm going to get my sand/walnut shell blaster going and the extra capacity of this compressor will really make a big difference.

Got a little further along on WillieB's engine today, I had already finished and cleaned the head so I went ahead and bolted it on and torqued it down properly.

I still have to adjust the valves and install the distributor drive, then set the starting timing.

I also have a little more to do on the front end, the gaskets I've been waiting for came in late this afternoon. Chances are I'll have it all buttoned up tomorrow and get it mounted in the engine stand. I had to use my steel valve cover, I glued a new cork gasket on the one he shipped with it and I could not get the screws to start, I also could not get a spare alloy cover I had in stock to work, so I dug out some new nuts and my clean unused steel valve cover and tried one of those expensive silicone gaskets just to see how it works. I'll let you know.....

Tomorrow in the stand, then we'll see if it will make some good noises. I'll video the start up and run in, although after the first minute or so it doesn't make for compelling video just to watch it run at 2K RPM as I break in the cam.  ;D

[MiniDave]

Buttoned up a few more things, set the valve clearances and closed up the front of the motor, then I installed the radiator and got the engine loaded into the stand and mostly wired up.

Took quite a bit of fiddling to get the yellow fan blade not to hit, also the water pump pulley hit the cam belt cover, so I had to add a spacer inside the pulley between it and the pump. Then everything finally cleared ok.

Just a few more bits to hook up. Add oil, water and gasoline, then I'll crank up oil pressure and see if it will make some good noises.

I also need to weld the 02 bung into the muffler, then move a few things around and clean up a bit so I can get it to the back door for the exhaust to go out....

I have an exhaust hose but I don't think it's big enough to fit over the chrome end on the muffler - if I can get that sorted I can run with the back door mostly closed when it's really cold out.

[Jimini II]

Looking good Dave.

Maybe install a dryer vent flap in the wall and connect the exhaust hose to it when needed.

[MiniDave]

Or.....build my damn shop so I can put a proper exhaust vent in the wall?  77.gif

[MiniDave]

Alrighty then, cranked up oil pressure with no problem. All I need to do now is run down to the gas station and pick up some petrol.

Oh. I still need to weld in the O2 bung.....forgot about that.

It will run this afternoon for sure, then I can let it sit overnight and tomorrow retorque the head and reset the valve lash, then run it some more just for final checks.

Then if I can get it all loaded up again maybe they can come get it Friday......it should be home by Xmas!

[Willie_B]

Sounds like the starter really spins it over with no plugs. Looking forward to hearing it make the RIGHT kind of noises.

[Jimini II]

Or.....build my damn shop so I can put a proper exhaust vent in the wall?  77.gif

Well as the wifey said you are failing at retirement there should be no objections LOL.

[Jimini II]

Alrighty then, cranked up oil pressure with no problem. All I need to do now is run down to the gas station and pick up some petrol.

Oh. I still need to weld in the O2 bung.....forgot about that.

It will run this afternoon for sure, then I can let it sit overnight and tomorrow retorque the head and reset the valve lash, then run it some more just for final checks.

Then if I can get it all loaded up again maybe they can come get it Friday......it should be home by Xmas!

Or.....build my damn shop so I can put a proper exhaust vent in the wall?  77.gif

That's a solid oil pressure reading for just spinning over.

[MiniDave]

I have some different springs I can try if it's too high, but we'll see once it's running.....if it stays under 80 I'll probably leave it alone. I can also get more new springs from Vicky Brits (this one is new, along with the plunger) as I've found they vary considerably.

My green car was running really low pressure, a new spring and plunger and now it runs right where it should. It wasn't stuck, I think the spring just got weak somehow.

I filled the oil filter before I cranked it up so it didn't take a lot of cranking to get pressure - this was the second spin up.

[MiniDave]

It's alive!!!!!

At least it was.....I think my fuel pump quit on me.....again. It was an old pump that used to fail on the car I ran it on too, usually you could tap on it and it would start up again. This time - nope.

Next time I'll turn the camera sideways too - I hate when people post videos like this!   ;D

[BruceK]

It sounds great.  Got that new engine smell too I'm sure.

[MiniDave]

Oh yeah, smoked a bit for sure.....that silicone gasket didn't seal and leaked too - I went back with a cork one....at least I know those work.

Don't know why it quit yet, I'm going to retorque the head and adjust the valve lash then I'll fire it up again in the morning.