TheSamba.com :: View topic - My 1760 Stroker, the 1641, .... and the bastard

Thu Mar 08, 2018 12:22 pm

VW only used a thrust bearing in one side of the case. By installing a double thrust bearing, you are altering the design. The second thrust bearing was never ment to go in the second side. You what you are needing to do is alter the case or the bearing so it will fit.

Anytime you change what VW did you all have to alter parts. So unless you're building a stock engine with ALL NOS parts, expect to measure, alter, finesse, and be prepared to "fix" just about every part. And yes, that includes all the aftermarket parts even if they are supposed to be direct replacements of VW parts.

Fri Mar 09, 2018 4:31 am

I'm assuming that's a dig. A builder as opposed to an assembler. Wow. Ok, dude. I'm an idiot for not knowing that the parts I buy have to be modified before using. And if that's really a knock on me, well .......... I already admitted that I'm not good at figuring stuff out, so thanks for sharing!

Fri Mar 09, 2018 9:12 am

dennismcd707 wrote: I'm assuming that's a dig. A builder as opposed to an assembler. Wow. Ok, dude. I'm an idiot for not knowing that the parts I buy have to be modified before using. And if that's really a knock on me, well .......... I already admitted that I'm not good at figuring stuff out, so thanks for sharing!

Not a dig at all, in fact I give you props in taking the initiative to learn and build the engine yourself. Most dont even get to the 'assembler' stage and end up paying for someone to 'assemble' and end up with a short lived engine.

Take your time and keep asking, just dont get mad, frustrated yes, mad no.

he cam bearing issue is a real problem. In fact I only use NOS at the moment due to extremely poor fit and tolerance.

The good thing about crap parts is you learn so much more than you would have if the parts just went on with no issue.

Wed Mar 14, 2018 9:26 am

Frustrated, yea. Mad, no. Good advice. Which brings me to my next hoop. I was hoping to get a gland nut welded onto something before I began assembling my crank, but the stars weren't able to align in time, so I had to begin without the benefit of being horizontal for assembly. Oh well.

Now the problem I'm having seems to be the number four throw on my crank. No matter which connecting rod, bearing combo I throw at it, as soon as I "one hand snug" the ARP bolts on whichever conn. rod is on that throw, it starts to bind up. The rods are 4340 H-Beam's, which out of the box, with or without the ARP bolts screwed in, all weighed the same, with one being an oddball one gram heavier. One gram. I also measured their thickness, and they were all identical. And since I tried different rods on crank throw number four, and only number four binds up, I'm going to conclude the problem is with the crank.

so ....... I checked the journal for anything amiss. Nicks, burrs, dents. Nothing unusual. If the next measurement is the throw 'surface to surface' dimension, it will probably measure smaller than the others, I'm willing to bet. In which case, it's easier to lap my nice expensive rod until it fits nicely without binding, and then bring the others along to weigh the same. Have I forgotten anything, or is this the 'WRONG' approach?

Any ideas or suggestions are welcomed. Don't get mad ...... but you sure as hell can get frustrated. Otherwise you'd explode. Anyway, I'm going to install my oil control and pressure relief valves in my case, while I try to stop being frustrated, and think of the best answer to my connecting rod/crank problem.

Wed Mar 14, 2018 10:04 am

Once I modified the cam bearings with a small file blade, removing the unnecessary tab, they fit into the case just like they were meant to be there. :roll:

Here are my new oil pressure control valve and relief valve plugs/caps. What a great idea ... these things are pretty slick! Plus, they "both" actually came with brass washers/gaskets, not some cheap stuff. VW should have used these instead of the screw driver slotted ones. What a pain in the ass those are.

I'm still hoping to get this crank throw issue remedied soon. I did forget to mention, I did check with a feeler gage the side clearance. I could just get a 3 thou blade in on both sides of number four.

Wed Mar 14, 2018 11:10 am

the Allen relief plugs WERE used by VW, but not until the Mexi-beetles. They were developed after US production ceased.

I'll bet the radius on the 1 rod journal is too big. Try to magic marker the rod bearing, put it on and bind, rotate, and then remove. Marker gone? May be as simple as a bearing chamfer. This is very common with Chevy journals, less so with VW (but still happen)

Have you measured the journals and rod big end ID?

Wed Mar 14, 2018 3:08 pm

The allen head relief plugs were lllLLLOOONNNGGG (LONG) overdue, and I have to order 4 more. I like 'em!

I don't like the trouble I'm still having, though. I'm still stuck on number four crank throw issues. I put a chamfer (or a larger 'break edge') on the sides of the bearings and knew for sure that 'THAT' was going to be a slick fix, thank you John! Well, nothing changed. I put magic marker on the radius on the crank, installed the bearing on the rod, and then the rod on the crank throw (dry). I started to tighten the bolts, and kept a feel on the rod. I got close to tight, not even all the way snug (there was still a very small gap between the rod and cap), and she started to bind again. But nothing seemed to touch the radius on the crank. The magic marker is still there, and not smudged. The photos are helpful in that I can see much better what's going on.

Journal diam. and big end rod diam. are okay.......

So, I took it apart, snapped some photos, then had an idea. The rods were .891 thick, so I put together some gage blocks measuring .896 and tried to fit it inside (on the crank throw between the flanges) where the bearing would go. I would expect a tight fit, and it was. Really tight. So am I lapping my rods to remove material, or am I removing material from the crank? I'm not sure. I doubt I'm touching the crank. I did measure the journal diameters, and if anything, a few of them are bigger than max size by a few tenths, but I dismissed this as 'NOT' the problem.

Any more ideas? It's an Empi crank ...... 4140 forged 74mm stroker, brand new.

Wed Mar 14, 2018 3:12 pm

try getting your rods and caps tight before you insert the bolts

Wed Mar 14, 2018 3:48 pm

I already know that I can't. Plus, when it starts to get close, I need the ratchet. I think I'm gonna try installing the bearing on the rod, snug the cap, and then take some sandpaper and start removing bearing material.....thus opening up the rod I.D.......a little at a time, and see if it fits better, with no binding.

Wed Mar 14, 2018 3:55 pm

.....and if I open it up too much, I have another set. This way I'm eliminating the journal diameter as being the problem. (or the bearing I.D.)

Wed Mar 14, 2018 5:01 pm

Do you have a micrometer man? Then you can check that instead of sanding down a bearing. I just got a set on Amazon for $60. They really are necessary for building an engine.

Wed Mar 14, 2018 5:55 pm

Yes sir, I have mics. I use them too. Dial calipers as well. Gage Blocks, surface plate, depth mics, telescoping gages, travel indicators, transfer stand, test indicator, v-blocks, 1-2-3 blocks......... let's see, what am I forgetting? Oh yea, machinist parallels too. What do you need to know? When I mic'd the crank journal, it seemed to be a few tenths too big. I have 2.164 and 1 tenth as the low limit, and 2.164 and 9 tenths as the high. (on a new crank) My number four measured 2.165 and a few tenths. But how accurate am I really getting? (within a thou, I'm sure) My rods measured about 2.167 with dial calipers, and without torquing down all the way. Just real snug. The tolerance there is supposed to be 2.1646 to 2.1654

So thanks for the input. I'm still stumped. I had to take a break for now.

Wed Mar 14, 2018 6:13 pm

swap the crank for another one, or have the journal polished so it's within tolerance. Par for the course.

Thu Mar 15, 2018 3:18 am

Looks like a polish job it is. Sending the crank back to California seems like a headache that can be avoided. I also thought about switching over to the other new crank I have, in which case I'd be assembling the 1641 engine.

If getting the 74mm crank serviceable is going to take too long, I think I'll at least prepare the crank assembly on my brand new cast Scat 69mm C.W. crank. If the rods go on without any problems (they're brand new 4140 I-Beam rods), I may switch up and decide to build the engine with the Scat crank, and I'll put this 1760 on hold until the crank issue gets sorted out. If I can polish it back in spec, great. If not, not so great. :cry:

Like you said John, this kinda thing happens. Well, it's off to work for the next 3 days, and I'll be back on 'engine duty' on Sunday morning, bright and early. :vw:

Mon Mar 19, 2018 1:45 pm

This is getting funny .... I think. While my new Empi 74mm crank is getting serviced due to awesome quality standards .....NOT! (thank you Empi and thank you fat Performance in sunny CA. You sold me a crank that's out of tolerance!), I switched over and started to assemble my new Scat 69mm crank, along with my new Empi I-beam rods that I bought for it. (This is for the other engine that I'm building now suddenly, the 1641).

I measured all of the journals on the crank, and wow man, they're all on the money! Next .... I was ready to inspect the rods before installing the bearings and taking some measurements, when I realized I couldn't get the bolts out of the caps. They're really torqued down! I was going to wrap them up with some soft rags and put them in a vise so I could apply some leverage to the rod bolts ......... BUT I DON'T HAVE A VISE! Again, I'm stuck.

.............So, I just ordered a bench vise from Amazon. It will be here on Wednesday. I'm also going to start a build thread for my 1641 engine with the Scat crank I just mentioned. Like you said John, it could get very confusing here when I start talking about multiple engines, so I'll 'try' and only talk about the 1760 engine here on this thread. I already confuse people with the way I write down stuff that's in my head. No sense making it worse.

Mon Mar 19, 2018 4:07 pm

Dont feel bad, its a sad time in VW parts history. VW has turned its back on the air cooled market and the aftermarket doesnt have the QC standards we were accustomed to. For the new guys trying to open a new parts shop based on what is available now is going to be a struggle. Without specializing in a high margin service, hoping that parts alone will keep them going will definitely be an uphill battle.

Ive been building a few different engines over the past 5 years or so and the struggle is the same. On the 74x88 build the only parts that are the same from the beginning are the cylinders, heads and case. EMPI crank had the same issue as yours, AA pistons had wrist pins that had issues, AA rods...were AA rods, cam was OK but its matching lifters weighed a TON, flywheel had too much run out, not to mention several sets of bearings to dial it all in. Would it have run? with exception of the rod journal issue, yes. How long would it last? Its a roll of the dice, but can say it will not be a 50K mile build.

After knowing what it takes to build an engine, the places that sell 'all new' 1600s really make you wonder. I doubt they are taking the time needed to rework all those parts. Most VW owners have no idea what it takes to build a reliable engine these days with what is available.

IMO the term 'cheap' can no longer be said about our beloved VWs.

Reliable = Expensive, Fast = Really Expensive, Fast AND Reliable = No Budget.

Wed Mar 21, 2018 6:56 am

.....by the way, I forgot to say thanks to the Pruneman99 for his explanation on the cam bearing issue I was having. Well explained. AlteWagen as well. A clearer picture makes everything better.

Well, I dropped off my crank this morning to get fixed. With a name like "CRANKSHAFT CRAFTSMEN", you know it's gotta be a good jam, I mean, machine shop. They're going to actually make sure that all of the journals are in tolerance. What a concept! (Thanks Empi!) Then they're going to check runout and balance as well. They quoted me about 150 bucks and it would take a week or so to get to it.

So .... in going along with the recent theme of this thread (TAKE WHAT YOU'RE GIVEN, AND THEN DO YOUR BEST TO MAKE IT WORK PROPERLY...and then don't get mad either, life is too short!) .... I think I'll go weigh all of my pistons, do another inventory of all of my parts, and then start cleaning some tin. I've been leaning towards just buying a whole new set of black powder coated tin. Since everything else on the engine will be brand new, why use used tin? Then I'm concerned about buying cheap stuff that doesn't fit right. But ......... that's par for the course, am I right? I still have my stock tin if needed, albeit dented, rusty, and deformed.

Par for the course :lol:

Wed Mar 21, 2018 4:10 pm

Save and rework your german cylinder head tin. What shroud you use will depend on if you are using your stock heater system. Exhaust system will determine what lower tin will fit. Rear tin will be determined by both the above.

Wed Mar 21, 2018 4:49 pm

Someone else just posted about the EMPI cranks and how bad they've gotten lately. It a bummer that you need to spend 150 bucks fixing a new part.

I'm going to drop a case off tomorrow at the machine shop. If It checks good, I'll be crank shopping. Hopefully they have some in house we can measure before I lay out the $$$.

Keep at your build. You will get there. Just remember to check every part and don't rush.

Thu Mar 22, 2018 4:50 am

Since rebuilding an engine makes you deal with outside sources, I thought it would be worth noting to write about the differences in the way places do business. I had bought the more expensive forged Mahle 87mm slip in P & C's from fat performance, and they came to me in a box that was all smashed up. Inside the box, each set was wrapped in plastic, and at the bottom I found a little baggie of wrist pin circlips. All was well, until I received my less expensive cast Mahle 87mm slip in P & C's from AirCooled.net. The box was whole and not damaged, inside the box somebody had taped the little baggie of circlips to the inside of the box so they couldn't become lost. Next, each set was wrapped in plastic, and then wrapped again in paper for damage protection.

There was a noticable difference between the way these two identical products arrived, and I had to mention it. One was packaged with care and good planning (by the folks at AC.N), and one was just shoved out the door and onto a FedEX truck. For this reason, fat Performance won't be getting another nickel of my money. C'mon man, is it just me? And don't blame FedEx.

Speaking of FedEx, the UPS man delivered a nice new Yost bench vise to the ol' homestead yesterday, which means I was able to finally have a way to hold my conn. rods steady while I broke the bolts loose. (direct from the Chinese factory......thank you Empi) Nice vise. I needed one badly anyway, so ....

Next up, I weighed the pistons. They were all the same weight except one was one gram lighter than the others. They look pretty nice too. I see I won't have to modify them at all due to my bigger crank, because the skirts are already tiny. These are forged pistons and more expensive than the cast ones I bought for the 1641.

.....and lastly, I installed the cam gear onto my Engle W-100 camshaft. The directions that came with the new cam stated that the 3 bolts should be coated with Loctite and torqued to 18 ft. pounds. This is not easy to do when you're alone. How do I hold it while I torque it? Hmmm...... it was ugly, but I did it. Also, I had a choice between red Loctite 271 and 272. I chose 272 because it's designed for higher temps.

this is fun, but I still feel in the back of my mind that I need to hurry