The 1641 for my Detroit money pit

[dennismcd707]

This thread will be all about the 1641 engine that I’m building. It will serve as one of two engines that I’m putting together for my bright orange money pit/sand rail/pleasure craft vehicle that I’ll be towing around Michigan for the foreseeable future. Two threads for two engines. The other engine’s crankshaft had to be fixed, so while I’m waiting on that, I thought I’d put some time in on this one.

Here is a list of the innards (all pieces are brand new so far, including the case: 1) Scat 69mm cast counter weighted & balanced crank 2) 4140 I-Beam conn. rods 3) Eagle “cheater cam:2280” by C.B. Perf. 4) cast 87mm slip in Mahle P & C’s 5) AC.N’s ‘STOCKER PLUS’ L3 heads (stock valves, 1.1 stock rockers, ported heads) 6) Pertronix Flame Thrower ‘pointless’ dizzy 7) center mount progressive 2 barrel (Weber/Holley 5200/Motorcraft DFV) full flowed with a remote filter 9) and finally, used dual exhaust headers with cheap glass packs

I started the day by attempting to do some routine assembly procedures, but I didn't get very far. Out of the box, the ARP rod bolts were torqued down so much I had to put them in a vise to get them loose. I had that issue last week. Then I had to fight ‘em just to get the caps off the rods, ….but I persevered, and I did it. ONLY TO DO THIS BONE HEADED MOVE!

.... so this morning I decided to begin doing my plastigage “oil clearance checks”, forgetting about how difficult it was to get the caps on and off. I put my plastigage on my first rod and rod journal, the lowest one, then torqued it down to 32 foot pounds. I was so concerned with not moving the rod and smearing the plastigage, I just forgot that it might be a problem getting the cap off. Now I’m stuck because I can’t get the rod off the crank. I’m tapping on it and pulling and wiggling and tapping, and I don’t even see an opening big enough in the crack to even consider sticking something in there and prying the cap off. WTH? Why do I do this to myself? Any suggestions on getting the rod and cap separated?

[67rustavenger]

Put the rod bolts back in the rods loosely leave space between the bolt and the rod and tap the heads of the bolts.
That will pop the rod cap loose.

Good Luck.
_________________
I have learned over the years.
Cheap parts are gonna disappoint you.
Buy Once, Cry Once!

There's never enough time to do it right the first time. But there's always enough time to do it thrice.
GFY's Xevin and VW_Jimbo!

[modok]

Yeah thread the bolts in halfway and use an aluminum or brass drift and a hammer to TAP them off.

GOOD IDEA to check the clearances, but sorry it looks like plastiguage probably isn't going to work, this time.

[dennismcd707]

I'm gonna try that first thing in the morning. I'm sure it's gonna work. Thanks again theSamba for coming to the rescue. I tried to explain to my wife how things work on here, and she nodded, but I don't think she really understands how helpful this shared knowledge stuff really is to us hobbyists who find themselves 'STUCK' all the time!

Funny thing too. When I first ordered my rods through ACN, I didn't open up the box right away, so I didn't know what ARP bolts were for my connecting rods. Then, when I first saw my rod bolts, I panicked. I didn't have a special "ARP" socket (whatever that was, chuckle chuckle). I had never seen bolts that looked like that, so I assumed that these must be what ARP bolts are, and they need ARP sockets.

What was I thinking? I emailed John at ACN and said "Dude, you sold me bolts but didn't tell me I needed a special socket!" He explained that they're regular bolts, you just have to use a 12 point socket on there, (or whatever the number is). I felt pretty dumb, but you have to admit, it's kind of funny.

[dennismcd707]

Success! As soon as it was suggested, I wondered why I didn't think of that. No problems, came right off. And ............... the plastigage was still intact. (thou and a half, or there abouts) I'm going to continue on, but no more plastigage tests!

So, since it's a new case, I had to buy all new hardware, including cylinder studs. I just opened up my package of new studs (8mm x std. length) and I'm about to install them. According to the Tom Wilson book, they go in finger tight, but not bottomed out. Also, he suggests I use permatex 3H on the threads to prevent oil leaks. Well, I'm about to follow directions, but I was just curious. Once they're in , they wiggle pretty good, as if they're not the right ones. Am I being paranoid, or are they supposed to wiggle up and down and side to side a bit?

[dennismcd707]

Got a few things done the last couple of days. After I watched a couple of videos and read up on how the full flow system all works, I drilled and tapped the new case for full flow, then I used my 4 ½ inch angle grinder to grind down the boss right next to the new oil pathway. Now there’s room for the 90 deg. fitting to be installed. Next, I washed it with dish soap and water, and made sure I left no chips or dirty sox behind.

I finished the crank assembly once I got the rod and cap separated (from yesterday). Actually, I had that done before I even finished my 1st morning coffee. I was eager, to say the least. Then I moved on to the installation of my distributor’s drive pinion and shims. Of course, I had to sand down the brand new pinion because it wouldn’t fit in the hole.

Before I started sanding though, I checked to see if the dizzy bore hole in the case was too small (since it’s a brand new case). To check, I just tried using an old dizzy drive pinion that I had from another engine that I took apart, and sure enough, it dropped right into the case like it’s supposed to. So ……….. I sanded and sanded until the new one fit.

According to the Tom Wilson VW engine book, now’s the time to set the end play on the distributor drive shaft, not ‘after’ the case is glued shut, and that makes sense to me. Right out of high school back in the 80’s, I dropped a washer down the hole and had to split the case to get it! That was my very first VW build! Ha ha, my buddy never let me forget that, I tell ya.

Anyway, it calls for a gap of .020 to .050, (should be .006 to .020, right?) and after 3 shims, my gap is still .090……..and I’m out of shims. So guess what? I’m stuck again. I ordered some on Amazon and they’ll be here in 2 days.

Next, I installed my oil pressure relief valve and control valve, but again made the smart choice and replaced the old slotted type plugs with allen relief plugs. Man I love these things. Anyway, I was sure to lube up the little pistons with oil and white grease, then I oiled the springs, put a few drops of clean oil down the hole, then I sealed the plugs using just a smidge of permatex under the brass or copper washer (which is it?). I probably shouldn’t have used anything with the washer, but I did anyway.

Then I switched gears and installed all of my new cylinder studs. Again, I read up on the installation process, and saw a bunch of conflicting ‘stuff’, mostly here on theSamba. Right or wrong, this is what I did. I put a few drops of blue Loctite on the threads, screwed ‘em in till they bottomed out, backed ‘em out a few turns, then brushed the studs with permatex 3h and tightened them again, just hand tight. After 24hrs, they should be good to go. The Loctite keeps ‘em from moving (in theory) and the permatex 3h keeps ‘em from leaking (in a perfect world).

I think I might try my hand at rebuilding a carb tomorrow. I bought a kit, some carb cleaner, loud music, I should be good to go til my shims get here on Wed. Then I'll continue on and put the crank and cam in the case and slam 'er shut. I'm kidding. (This "IS" slow.)I've since learned that this end play tolerance is excessive, and should be .006 to .020.

[dennismcd707]

Before inserting the cam bearings into the case, I got rid of the tab on one of the two cam thrust bearings. I used a small metal file and it took all of five minutes, but without doing this, it’s impossible to install the thrust bearing. I didn’t know this during an earlier build. I got angry and panicked…. Then, in 3 simple sentences, I understood exactly why I had to alter the bearing to fit the case.

” 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 meant to go in the second side of the case.”

Anyway, I put the cam bearings in and they fit nice and snug. Next I measured the main bearing dowels, just to be sure they were all the same, and I put ‘em in their respective holes, 4 in one side of the case and 1 in the other. Now it’s on to putting bearings #1, #2, and #4 into the case and torquing it down so I can take some measurements. I can't do #3 because it's already installed on my crank. (...sidenote: Having this installed on my crank also prevents me from being able to do a few quality checks, such as using the engine case instead of bench centers or vee blocks to check my run-out.)

I actually broke down and ordered a 1.4” to 6” dial bore gauge yesterday on Amazon. I figured that with all the time and money that I’m putting into these engines, it’s easy to justify one more expense. Gonna do it, so I might as well do it right (or close to it). Life is short. I’ve waited 30 years to build my second air cooled VW engine, so in my eyes, I’m gonna build it (and spend $$) the way I want to. See? Justification!

I also wanted to add these last two photos. I was careful when I installed my new cylinder studs so as to not get any permatex on the case deck surface. This machined surface is clean and ding free, the way it’s supposed to be. My earlier photo made it look like I was kinda sloppy. Normally true, but not here. Too important. I also had asked if my cyl. studs were supposed to wiggle once threaded all the way in. They did quite a bit, in my opinion, that's why I asked the question. (nobody replied) ...........anyway, they tightened up once the Loctite and permatex 3h hardened up.

[dennismcd707]

To check tolerances, I placed the cam in and then studied the pile of oil pumps I had sitting on the bench. After reading up on oil pumps this morning, I decided to go with a stock oil pump. Some guys use the bigger one, some guys just won't. Right or wrong, I want to mock this up, but to do so, I have to figure out my "lost hardware".

It's a new case, and fat Performance in sunny CA didn't send me any hardware to go with it. I've since bought a case hardware kit, but which bolt, nut, and stud goes where, I don't know ....... yet. I'm figuring that out now.

I tried searching, and just opened up more and more searches. The oil pump studs are 8mm, and from what I've read, won't thread in by hand. They're initially very tight. I think I can pick out the right ones for this, but since I'm using a special cover (by Empi....hooray ) for the full flow oil mod, I have to make sure the new studs will work with the oil pump cover, but it looks like they will.

I also know which two are the bottom engine mounting studs, and the smallest one is for the oil cooler, but the others? Any help? (The alt/gen pedestal studs are already in, so these others are for.....?)

Once I get the oil pump studs in, I want to make sure everything looks and feels good (oil pump and cam), and I'll close up the case and torque it down for the first time. Maybe I'll use some plastigage. More to come ..... soon.

[dustymojave]

One thing I want to point out at this time, is about the rotational position of the distributor pinion that the Wilson book tells you to use when assembling the engine. I haven't looked in the book lately, and all of my books of that sort are still stashed since the last house move, so I can't readily check it now.

IIRC, Wilson tells you to set the distributor drive pinion so the slot in the top is at right angle to the crank centerline/case split, then drop the crank assembly into the case with #1 rod at TDC and #2 rod at BDC. This will set the drive so the distributor rotor is off from its correct position of about 4:00 with the engine assembled. Again, IIRC, this will be about 1 tooth off from correct.
_________________
Richard
Offroading VW based cars since 1965
Tech Inspection 1963 - 2012 SCCA/SCORE/HDRA/MORE/MDR +
Retired from building Bajas, Fiberglass Buggies and Rails in the Mojave Desert. Also Sprints & Midgets, Dry Lakes, Road Race cars. All types New and Vintage
SoCalBajas Member
Kicked Cancer's A$$...1st and 2nd round...Fight ain't over yet.

[dennismcd707]

.....and wouldn't you know it? I dropped the crank and cam in it this morning, and then sealed the case. So .... It looks like my timing will be off a 'scosche'. (Skoshe?) That kinda blows!

[dennismcd707]

Link

[dustymojave]

Well since skoshe is Japanese, the spelling in Romaji (Euro-based writing as we are using here as opposed to Japanese characters) is whatever you make it, I suppose.

You COULD at this point remove the shaft and re-set it, keeping in mind that it will twist out and back in. Turn the engine over on its side as you had it when you dropped the crank in when you do this so the thrust shims will fall out instead of into the sump.
_________________
Richard
Offroading VW based cars since 1965
Tech Inspection 1963 - 2012 SCCA/SCORE/HDRA/MORE/MDR +
Retired from building Bajas, Fiberglass Buggies and Rails in the Mojave Desert. Also Sprints & Midgets, Dry Lakes, Road Race cars. All types New and Vintage
SoCalBajas Member
Kicked Cancer's A$$...1st and 2nd round...Fight ain't over yet.

[dennismcd707]

I thought about re-doing that part, but I'm dragging my feet. But really, now is the time to fix it, if any, wouldn't you agree? But ................ I can talk myself out of it too

[air-h2o-air]

wont hurt a thing but for possibly having plug wires in a different location on the dist cap....timing is still adjustable and can be set correctly

[dennismcd707]

Ok, so now after rereading what was initially going to be wrong with my timing, I'm confused. (Surprise!) I've followed directions from a couple of sources, and I think my timing should be good..... I think. Is it correct if the rotor points at 4 o'clock (with #1 at TDC) and incorrect (but runs fine) if the rotor points at 1 o'clock?

Is that my barometer on whether or not it was done correctly?

Mine is at 1, and it's gonna stay there. Vacuum can is in the right spot, hold down clamp holding down "AND" staying down. I think I'm good. I also have 5 shims under the drive gear, with probably no more than a ten to twelve THOU gap. Crank, cam, and oil pump are spinning freely, case is shut tight

.... now it's on to the recently painted breast plate tin. This has to be modified due to the 90 deg. fitting used for the full flow. Does anybody have any suggestions for this mod?

[dennismcd707]

....and of course, the next step isn't going too smoothly. I'm trying to join my new Scat crank with my new Empi flywheel. Stop laughing ...... I'll eventually get it. I've already read ten diff. threads on the subject, so I should be good. No seriously, stop laughing.
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1971 Super Beetle, 1776, dual Weber's, roller crank, big valve modified racing heads, close ratio trans, lowered suspension, 4 wheel disc brakes, car has over 368,000 actual miles. (RIP 1970 Beetle/Baja, 1986 GTI, 1999 Jetta, 2002 Jetta)

[modok]

We don't know if it was Karl Rabe or Dr. Porsche himself who decided to affix the crank with dowel pins, but whichever of them it was..... is surely burning in hell for it.

[dennismcd707]

....and speaking of Karl Rabe or Dr. Porsche burning in hell, that reminds me of a song. (In Hell I'll Be In Good Company, by The Dead South......)

So unless I'm talked out of it, I'm expecting in the mail today an 8mm 4 flute reamer, which will allow me to ream out the dowel holes in the new Empi flywheel. The holes appear to be a tad tight, using just my dial calipers. (not very accurate) My hope is to NOT MAKE THE HOLES TOO BIG....... but I'd sure like it to fit on the crank eventually.


Link

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1971 Super Beetle, 1776, dual Weber's, roller crank, big valve modified racing heads, close ratio trans, lowered suspension, 4 wheel disc brakes, car has over 368,000 actual miles. (RIP 1970 Beetle/Baja, 1986 GTI, 1999 Jetta, 2002 Jetta)

[Clatter]

Hi,
Nice work. Thanks for sharing.

I'd be pulling a shim out of that distributor drive..
When you have a shiny-China distributor clamp,
It's not holding that tight of a tolerance itself,
Being all kind of taco-shaped, and not even seated all the way..


It might end up seating one day, and take out all of your clearance?

Better a few extra thou clearance, than tightened all the way up..

_________________
Bus Motor Build

What’s That Noise?!?

[dennismcd707]

You may be right. But the funny thing is, I actually used this new cheap chrome plated dist. hold down clamp because it was brand new and actually had a good shape. Of the 3 other used ones that I have (all OEM), they're shot. Bent, crooked, smashed.....whatever, they're mostly junk. I do have another brand new clamp, an aluminum billet style clamp, but I think the one I'm using now is working ok.

I've had it off and on so many times, I can see it's holding the dist. down pretty good, and sitting almost flush with the case. (the picture is deceiving) I think I'll leave the clamp ...... but still, too many shims you think? If I were take one out, the endplay will be approx. 35 to 40 THOU. Better too loose, I understand, but that's much too loose I think. I could split the case again and stare at it. Sometimes that does something. (seriously, one way or another)
_________________
1971 Super Beetle, 1776, dual Weber's, roller crank, big valve modified racing heads, close ratio trans, lowered suspension, 4 wheel disc brakes, car has over 368,000 actual miles. (RIP 1970 Beetle/Baja, 1986 GTI, 1999 Jetta, 2002 Jetta)