A friend of mine took his Chevy Impala into a local GM dealer for service, claiming it had a vibration in the engine at certain speeds. The dealer techs confirmed the vibration and also noticed that the oil pressure light intermittently flickered on and off, mostly during idling. This seemed to go away as the engine RPM increased.
The service crew installed a new oil pressure sender, but that didn’t solve the problem. They checked the oil pressure, and although it was very low at idling, it came up enough at higher RPMs to be adequate. The engine ran fine, so they decided to concentrate on the vibration, which only occurred at certain RPMs and didn't change much whether it was being driven or free revved in the shop.
After a week of fruitless attempts to get rid of it by changing the damper, the alternator, the water pump, the power steering pump, and even the flywheel and torque converter, they were no closer to figuring out the problem. They returned the car, with a promise to look at it again once they heard back from GM. A week later, the engine made a horrible racket and died abruptly in traffic. The owner had the car towed back to the dealer, where the service crew tore it down and discovered the reason for the oil light, the vibration, and the sudden demise of the motor.
The crankshaft was broken in half. During initial assembly, someone had forgotten to install the center lower main bearing shell. The cast crankshaft had been flexing up and down at that point until it finally failed.
This entry was submitted by Dave James and edited by Rob Spiegel.
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@Rob- From what I've heard, Harley customer support is pretty good nowadays. The problem the magazine had was in the 80's...I believe HD was owned by AMF at the time, and it almost put them out of business.
That's an interesting story, Kenish. I always thought HD was better at customer support. I find it surprising they wouldn't take responsibility for a factory error, in or out of warrantee.
xti: Your comment above was funny ... the one about how this blog has morphed into a HEATHKIT subject. I suspect that there are more people who've experimented with building various HEATHKIT products in the past 40+ years than those who have had the center main bearing cap of their 350 Chevys missing!!!!! Now, IF it was a "4-bolt main" motor w/ a forged steel crank, ala Camaro & Corvette, then I suspect it might be still running! (Ha! Ha!)
I know HEATHKIT is "back in business", but it ain't the same HEATHKIT as we all knew so fondly, and therein lies the difference. I wonder how many HAMS are still using some of the those transceivers (SB ***), etal.? Or their scope kits, etc.?
xti: THANX very much for that info. I will pass it on. I do not know if they have the manuals yet, although comments were made that he did build all of this equipment from the kit products, and not as preassembled units. I know the amplifiers are heavy, and sit at the bottom of the 19" cabinet, but I do not know about the "internals" of the power amps. Although he was an excellent engineer in his day, they are older now, and I know he doesn't have any test equipment beyond a simple V-O-M, so I suspect that he'd just as soon send the units to someone w/ the proper audio generators, o-scopes, etc. to tune & adjust as necessary.
Regarding the speakers, I know he's already checked w/ a shop in this area, who specializes in speaker reconing, etc. I believe they told him to bring them in for inspection, and that IF they thought it would be more economical to replace w/ new ones than to recone the old ones, they would advise him.
Although the internet can be a GREAT "device" for searching, it can also be a giant black hole! I've gotten totally frustrated more than once myself doing google searches, only to end up with 4,000 "hits", NONE of which led me to a solution. I guess my online persona, OLD_CURMUDGEON is indeed a very accurate description. When it comes to manufacturers' product specs, I can't tear myself away from a printed catalog!
Wow - this seems to have turned into a Heathkit thread. I don`t know of anyone that still fixes Heathkits personally, but Heathkit still exists, and they apparently still have most of the manuals available. Go to Heathkit.com and send them an email.
They do not have repair parts, and do not repair old kits, however.
There seem to be lots of people that do repair old Heathkits, though. Just do a search online for `Heathkit Repair`.
Once you have the manuals, any decent tech should be able to repair one, though.
Speakers are easy to repair, you can also get foam repair kits online or through eBay.
A cautionary note to your friend, though. If the power amplifiers are the large 200W per channel ones, DO NOT ship them anywhere with the power transformers installed.
The transformers will tear out of the `chassis` and destroy the amplifier.
Personally, I wouldn't even drive them across town with the transformers installed.
A minor drop in the Living room can also be disastrous. They have a wire frame chassis that was an incredibly stupid piece of engineering - I don`t know what they were thinking. It seems to be made from old coathangers.
These amps also have an unusual output stage configuration. It is essential that you have a manual before attempting repairs.
The best thing to do with these amps is save the nice front panel and trash the rest of it.
Put the panel back in the rack and hide an old JBL 6260 or 6290 behind it. Your ears will be in heaven. 6200`s were some of the best amps ever made.
I remember that if you bought a Harley, you had to buy 2 = one to ride and one to strip for parts. And the local Harley distributor was convicted of being the ringleader of a price fixing scheme with other motorcycle shops. I have also been told that Honda is the abbreviation for "Harley Owners' Need Dependable Alternative". The last time I had my Moto Guzzi at the motorcycle shop I was looking at the Harley's and Gold Wings. One of the staff commented that the new Harleys had improved so much they were almost as good as a Honda. Harley does make a nice bike, but I just can't justify the premium paid for the name.
A friend has the entire HEATHKIT "PROFESSIONAL" rack & panel series of stereo equipment that he built in the 1970s, 1980s. Some of the chassis are in need of repair, including the midrange speakers. He claims that he had the name & tele. # of a former HEATHKIT technician in Michigan, who had a "side business" repairing HEATHKIT products. My question to you is, do you know anyone who currently is knowledgeable in legacy HEATHKIT products that he can send the items for repair & retuning?
The problem with the speakers is that the polyurethane foam "spring" at the edge of the cones has disintegrated, and so the speakers do not reproduce the sound correctly anymore. However, he told me once that there is a local speaker repair shop, so addressing that problem is not an issue. But, he doesn't want to invest in the speaker repair until he gets the remainder of the electronics repaired.
IF my memory serves me, they have the AM-FM tuner, the preamp, active crossover chassis, the base crossover, & two final amplifiers, one for the large bass speakers & the 2nd for the midrange & tweeter speakers. The speaker enclosures are the (6ft) tall cabinets that HEATHKIT sold.
Thanks for your thoughts. The driver transistor is a diamond package 2N3055 NPN that uses a mica insulator. It looked good but, may have a flaw or puncture that would result in path to ground that could destroy the 2N3055, the small signal NPN, and the regulator chip. I'll replace the blown stuff and install a new mica insulator. I'll let you know what happens. Thanks again for the tip.
Make sure that the outputs are the correct Heath parts. They may have been swapped out for devices with higher drive requirements.
We did have a run of TI MJ-802 output transistors in AR-1500 receivers that did not meet spec. We had to go into every kit in stock and put in a giant red notice, along with a bag of new Motorola replacements to prevent the ensuing carnage if the TI ones were used.
It wasn't practical to remove the TI ones from the package, as they were buried too deep. I never saw any kits come back because of this probem, so I guess everyone read the notice.
It's possible that the same thing happened with the IP-2715. The 2715 came out toward the end of my time with Heathkit however, so I'm unaware of that actually being an issue.
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