1776 build - questions

[Zcat7]

I'm in the middle of building my 1776 engine since finding that my "original" Brazilian AS41 case was cracked. I plumped for an Auto Linea aluminium case, already prepped for 1776 barrels and am using most of the other hardware from my 1641 setup (it was very low mileage before the case went).

The other thing I upgraded was the cam, opting for a Engle 100, which necessitated I switched to an early oil pump. When fitting the pump yesterday I was surprised to notice that even with the case fully torqued up the pump just slid into place. I was expecting an interference fit and even waited until I'd fitted the pump before final torquing the case.

Should I be worried about this? Is it likely to be the pump (Schadek) or the case? Will it be susceptible to leaks?

I've heard good (and a couple of less good) things about Auto Linea since buying the case so I'm hoping this isn't going to be a show stopper and I've made a wrong choice...

Neil

 

[Trikky2]

The oil pump should be a snug fit but not clamped by the case. Otherwise it would not be possible to remove the pump without separating the case halves.

Oil leaks are prevented by the gasket between the pump flange and the case.

It would be interesting if you could take some pictures and do a thread on your build since there is not much info on using these cases.

 

[Zcat7]

Well it is "snug" but I expected to have to drift it home. Since the first post i pulled the pump and trial fitted the old one; it wouldn't slide straight in... i then took vernier measurements around both pump housings and they were within 0.05mm of each other, which surprised me as I wouldn't have thought that would make the difference. So, I've been diligent with the gaskets and sealant and am going to stick with what I have (if you'll pardon the pun )

I have been taking some pictures so will post them if you think they would be useful.

Thanks Trikky

 

[K@rlos]

Auto Linea cases are very good and a lot stronger than an AS41 mag case but heavier too. The only thing I'd say is make sure it's spotlessly clean. They tend to have swarf left over from machining and sometimes need the insides cleaned up.

Honestly though they are very good cases but do need some fettling.

 

[Zcat7]

Part of the reason I went for aluminium was the strength; I didn't like my experience of the cracked case magnesium one. I think the ally is about 15 pounds heavier than a magnesium case, which is just under twice as heavy but I find it more reassuring, especially in bored out 1776 form.

I had heard about the swarf problem and I spent quite some time cleaning it before starting the build up, it was the "less good" thing I had heard. The other problems I have noted have obviously been that potentially the oil pump bore is slightly out (oversize) but also the oil pickup pipe is not centered properly in the aperture (which I didn't notice until I went to install the mesh filter, otherwise I'd have changed it for the original). It's close enough but slightly irritating. I have to agree though and say that in all other respects the case is impressive and the casting and finish is definitely better than my Brazillian AS41 in places.

 

[Zcat7]

Build piccies here. I'll keep it updated.

http://forum.earlybay.com/viewtopic.php?f=2&t=53981

Neil

 

[Trikky2]

Build piccies here. I'll keep it updated.

http://forum.earlybay.com/viewtopic.php?f=2&t=53981

Neil

Good stuff

 

[K@rlos]

My 2110 is assembled in an AS41 BUT I sourced an OG german case which any engine builder or VW guru will tell you the build quality is far superior than a Brazilian case.

 

[six]

i had to rebuild my engine. same case as yours. I had to pull the pump out. but when rebuilt and cleaned up its slid home with minor force. sounds like the same as mine tbh. its got 5k miles on it since rebuild and all is well. only arse was i had to bin the shroud as the builders had done an aweful job trimming it for the bubble top.

 

[six]

Auto Linea cases are very good and a lot stronger than an AS41 mag case but heavier too. The only thing I'd say is make sure it's spotlessly clean. They tend to have swarf left over from machining and sometimes need the insides cleaned up.

Honestly though they are very good cases but do need some fettling.

true that. the amount of swarf i took out of mine was scary. even after it had be done ! by the origional builder! well worth cleaning the gallies well

 

[Zcat7]

I must admit the talk of all this swarf does worry me. I visualise pulling the gauze filter out one day and seeing it prickled with shards of aluminium and curls of steel like pencil sharpenings. :shock: I washed the internals with degreaser so far as I could reach with a brush and then blew out the galleries with brake cleaner and air, again so far as i could reach. I've read that some people go to the lengths of drilling out every core plug and tapping them for blanking plugs so that they can rod every oil gallery but I hadn't banked on that when I bought the case and I'm too far down the road now. I guess I'll have to go with it now...

What's the "bubble top" Six? I don't follow what you mean

 

[six]

Ah the swarf I found was just in the oil galleries. Sounds like you should be OK. I made sure they were clean. I use rifle brushes.

Looking at Ur PIC my case is slightly different. Its got a extra bit of casting behind number 3. The bubble top or raised roof cases give a factory clearance of up to 82mm on the crank. Didn't know if all autolinea cases were like that.

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[Zcat7]

Fingers and toes crossed! I'd never heard of these humped cases, you learn something every day!

 

[six]

Makes my 78.8 mm crank look small. Resisted temptation to Max it out lol

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[Zcat7]

What are your thoughts on fitting the rear (flywheel) oil seal; just tap it home dry/with a wipe of oil or use some Curil T or Hermatite?

 

[six]

I have the special tool and wasn't that impressed. I use a smear of oil and a hammer. Tap it in gently until its in. Just make sure it goes in square.



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[Zcat7]

I hope to start the engine up in the next day or so but was thinking of fueling. The old engine was running on twin solex 40s, set up of course for 1641cc. Will they start the 1776 configuration OK? I guess I'll need to get it on a rolling road for best results but should I expect it to run without as it is?

 

[jonboylaw]

It will start fine as is but may need fatter mains when you get to rolling road it.


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[Zcat7]

The engine lives! I managed to start it yesterday on the workbench.

I cranked it over for about 40 seconds with the plugs out to get the oil pressure up before trying to run it. I think I may have flattened the battery a bit because it was really slow to crank with the plugs in and didn't sound like it stood a chance of firing when suddenly it sprang into life. It ran for about 5 mins, nice and smooth, before it ran out of petrol (makeshift tank) and when I tried to restart it I was back to the slow cranking. I tried another battery too but it was only a little better. Maybe the timing needs retarding and the mixture fettling as it didn't want to idle either. In fairness I just plopped the dizzy in at it's previous setting and didn't touch the carbs either as it was getting quite late by the time I had rigged up the harness and bolted up the gearbox etc.

I'm wondering about timing the engine now. Will it be different with the Engle 100 cam? Should I just aim for max advance (I have a 009 dizzy) or set it static to stock figures?

Will check the carbs out today and find out what jets I have. I'm running twin Solex/Kadron 40s. Calculations I did yesterday suggest that I should use 128 mains. These are the calculations I found on line to determine the carbs settings:

Cylinder cc - 1776/4 = 444

Carb size - Square root of (cylinder cc x 6000 rpm [theoretical max]) divided by 40 = 40 (good, because that's what I have! )
Choke size - Carb size times 40 divided by 50 = 32
Main Jet size - Choke size x 4 = 128

As always any advice on getting this to run sweet would be appreciated. Ultimately a rolling road session will be done but obviously I need to get it usable and run in first.

Neil

 

[Zcat7]

So, after some tinkering I got it to start and idle/rev nice. I set the carbs up and balanced them and set the timing at about 6 degrees BTDC (I have a crap strobe light and no rev counter connected), which was retarded from the original position and has made starting easier.

I then pulled a carb apart and found that I have 130 mains and 28 chokes/venturi. When I bought the carbs for my 1641 they had been running on another 1641 and had been set up for the engine apparently but I'm guessing this would give quite a rich mixture...?

I'd like some more advice before jumping in and buying bits that may turn out to be wrong so please chip in if you know your carb setups but for now it looks like I need to change the jets and chokes about a bit.