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  View original topic: 1776 First Build Help Please!
dentfreeimage Mon Mar 17, 2014 8:41 pm

Hello everyone, I am currently working on my first build a 1776dp and have a few questions that I will greatly appreciate some answers.

I have the short block assembled and it seems to be binding when the crank pulley key way is at 3 and it free's at 4, it's also doing the same thing at 8 and free's at 9. It seems to spin freely if spun fast, but binds if done slowly.

I bought dowel pins at a local shop and they measure 8.05mm x 5mm.
The case was line bored and I am not sure if I need different size dowel pins. The case is stamped 040 on the flywheel area.

Also one of the pin bores was machined oversize and a replacement pin was included, but it was longer than the stock pins and I ground it to have the same measurement out.

The cam spins freely and there is no contact with the gear bolts, oil pump has proper clearance and I removed the cover to make sure it was not binding and the clearance between gears and cover is .003.

I also have a question about the head studs, I have one case stud which sits deeper and I have a total of 16 studs small, medium and large ones and don't know which one goes on the deeper hole.

What size of oil pump cover studs do you recommend for a 26mm pump with a full flow cover, my studs seem to be for an original pump and the studs have only 3 threads showing, hardly enough for a nut without the washer.

Greatly appreciate the help!



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Danwvw Mon Mar 17, 2014 9:03 pm

I had a case once that was a little warped and if I loosened certain of the large case nut's it would free up the crank which was binding. I would try to get the best looseness that way then finish assembly and it was fine, But I would not recommend this really. I suppose if your in question about the dowel pin's you should disassemble your engine and check to see that they aren't leaving an impression on the bearings. If your crankshaft is not good and straight it could cause it too. Have you installed the distributor and drive gear yet? That can do it too if it's only a minor binding. If it's pushing the drive gear up then it's not properly seated. Never force fit a distributor gear drive it should just skip until it drops into the brass gear then stay down without binding or pushing back up when the crank is turned. Do you have the pistons and cylinders on yet or is it binding without them? Oh, as far as the oil pump, You need to get the right one for your type of cam. If it is a 3 bolt cam you need the early oil pump style If you have a 4 bolt dished cam as came in the later type 1 engines then you need a different oil pump for them. (Not sure what stud length the oil pump needs? I would just pull one and get 4 a little longer from the local auto parts store.) As far as the cylinder studs go It kind of depends on if you have a early case that has been modified on the #3 top left stud in which case you need to source another long stud for it, Otherwise you can figure them out once you have the head in place. The bottom ones are all long.
Here is a link to a photo of my engine it has 10mm studs and the shortest studs look like they are on the top inside positions!

https://www.thesamba.com/vw/gallery/pix/1091025.jpg

dentfreeimage Mon Mar 17, 2014 10:05 pm

Dan thank you for your reply. The distributor and gear are not installed yet. Also the pistons and cylinder are not installed. The studs are 8mm and the one that has been modified is the #3 cylinder top closest to the tranny bell housing. As far as the pump goes, I am using an aftermarket cam and have a 26 mm empi pump to match it.
Can I pull the oil pump studs from the outside using some pliers and do the new ones install by hand finger tight?

The crank has been cut 20/20 and the block was line bored and honed by brothers. Also the rotating assembly was dynamically balanced.
I am planing on splitting the case anyways since I used Gasgacinch gasket sealer and I did not like how fast that stuff dries, it took me about 20 minutes to torque things down and the sealer was almost hard by then. I am going to give Permatex Aviation sealer a shot next time. Thanks!

sambabus Mon Mar 17, 2014 10:24 pm

X2 what Dan said, don't turn it over without the distributor.

Danwvw Mon Mar 17, 2014 10:32 pm

Sounds like a lot of work to replace that case sealer I noticed the same thing with mine even faster and it took me at least 20 minutes. You have got to see why it's binding though as they don't bind if right. I don't care much for the Aviation stuff. I used to use Permatex #2 years ago it always seemed to leak a little somewhere and it can be difficult to split the case after a few years. The modern case sealers are pretty good, I used some gray stuff (pretty fast drying though) I found at NAPA. It worked fine and is easy to disassemble. Permatex Ultra Gray may be a good one. (Think it's pretty fast though). Yeah, Take a look inside and see if it's a dowel. You can probably figure it out during a mock up without any case sealer. Did you use assembly grease on the crank bearings? That's pretty important! While you have it apart use just one half of the case and inspect the oil pump fit into the cam slot it should fully engage but not bottom out and walk around when the cam turns. It needs to clear the cam bolts. If that is what is hitting then your going to need to grind something down a little or find different cam bolts or oil pump. In fact you may be able to determine this when you pull the oil pump before splitting the case then grind the pump body down where the cam bolts were hitting. You may need a oil pump puller tool too, your going to have to pull the oil pump to get the oil pump studs out of the case. They will be pretty tight in there and your going to have to use 2 nuts on one stud and lock them against each other to remove the studs.

[email protected] Mon Mar 17, 2014 10:39 pm

DO NOT USE RTV FOR CASE HALF SEALANT!

While Permatex works, I think it was best used in the 1970s. Nowadays there are far better sealants (Curil T or K, Yamabond, Hondabond, etc).

I use Curil, it never hardens and cleans up very easy with alcohol if you have to take it apart to fix something. Permatex is a biatch to clean, which is one reason I can't stand it.

Danwvw Mon Mar 17, 2014 10:41 pm

sambabus wrote: X2 what Dan said, don't turn it over without the distributor.
Without the drive gear installed it's ok to turn it over. Most install this gear before case assembly, I always did it after. You just need to drop in the 2 drive gear washers which can be done by using some axle grease on the drive gear and between the washers to stick them in place or slip them down a long screwdriver shank that you have already inserted. It's risky!

And Yes if Permatex ultra gray is an RTV then don't use it. I would go with Johns recommendations.

jfats808 Tue Mar 18, 2014 1:22 am

You can measure the nut, plate and oil pump housing thickness to decipher how much turns you need to double nut the studs out. I would red locktite the case side after you figure that out and let it set. If the current studs dont work, you can use threaded 8mm 1.25 pitch rod and cut to size. Ive been using aviation permatex for years and it works just fine for me. A rag and carb cleaner will clean it up just fine. After sealing and final torqueing, thats what i use to wipe the seams.

dentfreeimage Tue Mar 18, 2014 6:09 am

I have been thinking about the order every went back together and I noticed on the case half with the crank and cam that it was a little tight to spin pushing on the rods and I lube the gears and got it going, but noticed the cam lifting from the opposite side of the gear at the same spot every time I came around . It was not bad enough for it to jump out of place or skip timing, my thoughts were since it has no pressure from the other half of the case, it would be ok once bolted down.

I torque the case main nuts to 25 lb and the hardware to 22 lb which I think is not correct since I have an 8mm case, will need to verify this. Also on the new oversize dowel pin, I made sure it measure the same or maybe a tad less than the others and when assembled the crank bearing fitted properly and the I could feel the dowel locking the bearing keeping it from spinning.

The cam bolts were ground down a bit also a bit on the back of the pump with no clearance issues after that. I am using double thrust cam bearings and I sanded the sides using sand paper and a flat sheet of glass and the cam spun free on the case before installing the crank.

pigzsnout Tue Mar 18, 2014 9:20 am

my 2085cc motor pre-assembly presented similar problems when I built it. I could not, for the life of me figure out why. I finally discovered that my crank gear was warped due to the shear key being to big, therefore it stretched the crank gear resulting in the gear being out of round. Everytime that high spot contacted the cam gear it would bind up.
I was using a stock german key, and a Chinese gear. I switched the gear to a NOS german gear and the problem went away. Would've never thought that key way machined surface would be a different size.

dentfreeimage Tue Mar 18, 2014 11:07 am

Thanks for the advice pigznout! I will go over everything and if all that looks good I may have a problem with this cam gear as well. It's straight cut Chinese set and during installation I had the drive part of it into place with a hammer and a large socket. This may be the issue, thanks again.

Danwvw Tue Mar 18, 2014 2:12 pm

Sounds like your on the right track with the cam gear. Unless your going to run it over 6000 RPM racing it or something, I would just use used Stock German cam and crank gears.

[email protected] Tue Mar 18, 2014 2:25 pm

you are wasting a limited budget if you are buying straight cuts for a 1776, they are completely unnecessary. Especially the Chinese ones that cause more problems than they solve.

dentfreeimage Tue Mar 18, 2014 3:35 pm

Thanks for the advice, if I have to replace the gears I will stick with stock style Engle or Scat for my SLR cam. I bought most of the components as a package and the gears were included.
Do you guys recommend using the kitchen oven to heat up the gears? That's what I did but I only let them warm up for 5 to 10 minutes at 250 degrees and I don't think they expanded enough since they got stuck about half way down the crank!

dentfreeimage Tue Mar 18, 2014 10:30 pm

Well guys, I think I found the solution to the problem. I think I over tightened the case. Before I split the case I went around and removed all the case hardware and left the main nuts finger tight. I then partially split the case and went back to torque the main nuts to proper specs. After that I was able to spin the assembly using the crank pulley and one hand with no binding at all. I then spit the case and found out the condition of the cam bearings and it makes me wonder if these were bad bearings or over tightening the case caused the problem?

Found a video on youtube about problems with the rotating assembly and it pointed to check first end play, which I had no problems with. Then it advice to check and make sure the crank gear does not walk away as it spins and the last thing it pointed was cam bearings binding.

I included pictures of my cam bearings and it looks to me like the bearings on the crank and cam side of the case had some binding on the thrust bearing and also on the rear bearing on that same side. The bearings on the other side of the case did not look bad at all. Is this normal wearing of new bearings or are they damaged and need replacement? They are Silverline double thrust.
Thank you all for the help.




Danwvw Tue Mar 18, 2014 10:47 pm

It's alway good to use a rubber mallet and with the cam in the case strike (not too hard just once) the end of the cam that has the gear to seat it on the the cam double thrust bearing before putting the case haves together. Inspect position of the bearings after seating the thrust. I can't tell from the photo. But my guess is that the cam bearings are fine. Be sure to use assembly lube on the bearings. I would also check the cam gear run-out.



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