If this is your first visit, be sure to check out the FAQ by clicking the link above. You may have to register before you can post: click the register link above to proceed. To start viewing messages, select the forum that you want to visit from the selection below. |
|
|
Thread Tools | Display Modes |
#1
|
|||
|
|||
How NOT to build VW engines
Sheesh, some people. Maybe this little "article" will help someone avoid these pitfalls. Background: Dude wants to soup up his 1200cc single port, buys a ton of parts, big bore kit, new heads, etc.. basically everything new. Good start. He takes the heads to a race shop for porting, larger valves, the works. So far so good (I haven't inspected the heads). Then the shortblock goes to a reputable machine shop ( I use them occasionally). They line bore it, and they bore out the cam bearing saddles to accept bearings. (This is the old type 1200cc that had no cam bearings from the factory). They balance the crank and flywheel, do the 8-pinning to the flywheel, install new pressure plate and balance that too. Sounds ok, no? He gets all the parts back and his father-in-law assembles the engine. Probably the worst mistake of them all. He puts the engine in his car, starts it, hears a MASSIVE mechanical noise and yanks it out in a hurry, bvrings it to me. I tear into it, marking errors down as I learn more of what it ate. Ready? It came as a longblock, all cooling stuff and induction components already removed, so can't say what those were like. So here's what I found. You may see that I'm a bit picky in some areas, but some of these things were just too unbelievable... lol.. Here we go: 1. I am tempted to turn the engine over on a bench, with the starter. I turn it over by hand several times, and feel something weird at every TDC. Hmm. I pass on the starter test and jump directly to dismantling. 2. I pop off the valve covers. Geometry leaves some room for improvement. I find solid screws, shims under the rocker towers, and original 1200 push rods (weak as hell IMHO) 3. I remove head nuts in the proper sequence. I don't bother to check what torque they required. Most were pretty much equal. No sealant was used with the lower 4. 4. I pull the head off. Wow, it came off easy. What's this? Large copper crush gaskets at the step where the FINS of the cylinder begin. WTF? he used the crush gasket to seal the head to the cylinder, but not at the combustion chamber joint.. but at the fins After carefully measuring distances here and there, I am able to determine that the cylinder mating surface hardly met the combustion chamber counterpart. Jeeez. This gap was there so the cylinder would DEFINITELY mate with the head at the right spot. Inside the combustion chamber. he eliminated it. 5. There was a paper gasket at the base of the cylinder. VW says to eliminate it and use sealant. There was sealant between gasket and case, but not between gasket and cylinder. 6. Deck height was too small to my liking. Assuming the cylinder would reach teh head mating surface. LOL. Did not measure CR yet, that should be interesting 7. Cylinders removed. Piston skirts show a little damage, found out why too... they've been hitting against the case, going in too deep at BDC NO WONDER IT WAS NOISY 8. 1 or 2 13mm case nuts missing. 9. Big 19mm case nuts way too loose. No sealant was used. (I use sealant here). 10. Oil pump cover nuts didn't reach more than half way through the nut. About to fall off. Great. Tiny 6mm nuts because it's the old style 6V 1200cc case. 11. Oil pan (Chrome, LOL) had only one gasket. Cover to strainer mating surface had no gasket, and no sealant was used anywhere. I was surprised to find original acorn nuts used however. 12. Flywheel. Clutch was wet with oil. Paper gasket between FW and crank was missing a chunk. Seal was pressed in properly, which was a surprise Three shims, two of them were nice, one had too big inner diameter, made larger with some kind of grinding tool that didn't even leave a round hole the shim was broken, and all chewed up and blue. Endplay was zero. GAG. 13. 8-pinning: no offset, and 3 pins were too long to my liking, possibly interfering with the FW bolt washer. One was protruding very little, sitting way too deep. All were too loose to the flywheel, flywheel came off very easily. (8 pinning effort wasted there, IMHO) 14. Time to split the case. Glue is still sticky. Too much of it was used. A rubber cam plug was used, and sealant applied all over it quite liberally. 15. You know the big case studs in the middle? The later model engines have a rubber o-ring that goes around them, and get squished between the case halves to prevent oil leaks. The older cases like this, don't have a groove machined at the base of the stud saddle to accept the O-ring.. but O-rings were used anyway. In a space that was designed to acdcept only a thin coat of sealant. OUCH. They were all squished to bits, pieces sticking out and some of them fallen off. The rest was squished between the mating surfaces, all I can say it looked HORRIBLE, and it must have distorted the case. 16. cam bearings. There is no thrust bearing. Just flange-less normal bearing halves. 17. Crank end bearing, closest to the flywheel.. was first not aligned properly with the locator pin, and the case was tightened anyway.. pin left an indentation on the bearing surface. The bearing surface on the inside, shows a hairline crack in it where the pin-caused dimple is. Bearing had hardened glue particles in it. 18. there's glue, rubber and aluminum particles everywhere inside the case. I haven't measured or weighed the rods (stock 1200) yet, looks like someone tried to balance them. Rods have new wrist pin bushings. They felt good to the new pins. I haven't inspected the bearing surfaces on the crank or case. No idea what torque was used on rod bolts. All in all, looks like a total rebuild is in order after just a few seconds of running time, a new record maybe? LOL Sheesh. The story continues.. Jan |
Ads |
#2
|
|||
|
|||
Jan Andersson wrote: > All in all, looks like a total rebuild is in order after just a few > seconds of running time, a new record maybe? ---------------------------------------------- Nah. First off, you didn't find a pair of sunglasses inside the crankcase. No sunglasses, no record. Secondly, it actually ran. In fact, it sounds depressingly normal. Vee-dubs are easy, right :-) (Just ask Ryan Price; no brains required.) -Bob Hoover |
#3
|
|||
|
|||
|
Thread Tools | |
Display Modes | |
|
|
Similar Threads | ||||
Thread | Thread Starter | Forum | Replies | Last Post |
rec.autos.makers.chrysler FAQ, Part 3/6 | Dr. David Zatz | Chrysler | 0 | April 22nd 05 05:32 AM |
Ford's Mod Motors Are "Top-10 Engines"? | [email protected] | Ford Mustang | 14 | March 19th 05 04:53 PM |
T1 fuel injected engines vs T1 carbureted engines | Jens | VW air cooled | 6 | March 3rd 05 02:22 AM |
rec.autos.makers.chrysler FAQ, Part 3/6 | Dr. David Zatz | Chrysler | 0 | February 18th 05 05:33 AM |
Stupid question (was Changing the oil filter only) | Bill F | Technology | 20 | January 18th 05 09:57 PM |