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WestPundit
Saturday, August 19, 2006
 
VEV Logs, Installment #1:

Getting Ready

There has, since way back, been a central appeal to a Volvo beyond their rugged construction, and dedication to safety (something which all manufacturers share, in
these days). It’s their stone-axe simplicity. This was a quality that was lost, going into the ‘90s, with the FWD 850 series, and the 4VPC, twin cam, B234 engine.

Now a Volvo is pretty much a Ford, which is pretty much a Mazda. And you can’t work on any of them, or anyone else’s car, so why worry? Just send it to the mechanic (oops – technician).
Bosch
Actually, the B27/28 V6 engine, which Volvo shared with the likes of Peugeot, DeLorean, Alfa Romeo and other luminary brands, was a complex and unreliable piece of shit as well. But that’s another story. For the most part, up through the ‘80s, Volvos had a reputation for being very simple, and easy to maintain.

My ‘86 740 Turbo Wagon, with it’s B230FT motor, Aisin-Warner AW71 transmission and (I would assume) Dana 30 live rear axle, on leaf springs, could hardly be simpler, unless it was, say, an ordinary 740. But the turbo really doesn’t add that much complexity, or get in the way of maintenance. But it does create specific problems - read on.

Oh, and parts are stone cheap, particularly as European cars go. Like the transmission and rear end, the whole car is all built out of generic stuff. This keeps the costs down. But, like everything else, it pays to know where to shop. This is particularly true with European cars. G_d knows, I saved a fortune (or, more like it, avoided spending another fortune) on my Alfa Romeo by dealing with Alfa Ricambi in Pasadena (I believe they have moved to Fresno, and become AR Ricambi). In the case of this Volvo, it looks like the best prices are generally had at eEuroparts.com. Note that I do not yet have any personal experience with them. But the word on the street seems to be positive.

Oh, but then there’s the electrics – the Bosch electrics. And here’s where the owner throws snake eyes every time. A distributor cap at eEuroparts (the best price I’ve seen) is $40. A rebuilt starter is $115, with a $50 core. I can do a little bit better than this, but only because I know several rebuilders, But then again, this is not unique to Volvo, lots of cars use Bosch electrics, including the lowly Chrysler K-Car, of which I have owned many (and, IIRC, rebuilt starters were over $200 for).

Anyway, as for Bosch, this is at the center of my next few posts here, as the VEV has Bosch LH-Jetronic fuel injection. Again, we are talking simple, basic stuff. The LH-Jetronic is about the standard for all European cars of this vintage, and it is likely the one most auto techs learn first in school. And. If you understand the principles of electronic fuel injection, and engine management, this will present no surprises.

But sadly, there is no OBD II; that didn’t come along until a decade later. Further, I have not yet learned how to query the computer for error codes. [On a K-Car (also Bosch), you just toggle the ignition key a few times, and read the Morse-code-like flashes of the check engine light.]

Well, enough background, on to the meat of the story:

Considering its mileage and cosmetic condition, I paid something of a premium price for this car (north of $1K). This was largely based upon the fact that I just needed a car – any car, and had no means to shop for a car other than public transportation. (Background, for those of you in the hinterlands: a car, almost any car, in LA, with a clean, non-salvage title, current tags and smog certificate, and no gross mechanical problems, is worth about $800 as a baseline.)

This car has got a lot of problems. (I’ll post some pics in the next installment.) But, underneath it all, I sensed a vehicle with some basic mechanical integrity. And, as I stated earlier, I knew it was a car I could work on.

Well, first among those is the general operation of the thing. It had a chronic dying problem when I first got it. That turned out to be a matter of distributor connections arcing to ground. But, it still dies frequently. And further, the conditions under which it dies seem to be totally erratic. This is likely just bad electrical connections. Early Volvo 700’s were known for engine compartment wire harness problems, and the turbo especially, due to the extra under hood heat.
This is all stuff that, as a veteran Air Force technician, electronics engineer, and marine mechanic, I am quite qualified to handle. But this is also a BIG HUGE PAIN IN THE ASS. The only solace is that once it’s done (the way I do it) it is DONE. Yet I am trepidatious, as I know I am likely to find a whole lot of stuff which is even worse than whatever the factory did.

Just sorting this whole car out, electrically, is a job in itself. And I tell you. The Chilton manual I bought (ISBN 0-8019-8786-5), which proudly states, “INCLUDES WIRING AND VACUUM DIAGRAMS” on the cover, is of little use. [I actually got some real good (likely factory) diagrams off some .ru site – I have yet to scan my computer for malware.] If anyone has any good electrical or vacuum diagrams for the ’86 740 Turbo, I would greatly appreciate it if you would pass them along to me.

Now, on to the real mechanics - the stuff I’m sure you all were waiting for. ;)

Volvo only gives the owner of a B230 engined car 45Kmi between timing belt changes, and similar mileage between valve adjustments. Well, the car sounds like a sewing machine. And the previous owner couldn’t tell me the last time the timing belt was changed, so these things need to be done. But, the use of an intermediate shaft, and the RWD configuration of the 740, makes timing belt changes a breeze. Adjusting the valve clearance (on shimmed bucket tappets) is also an easy job, so long as you have the proper tools.

Ant, if you check eEuroparts the timing belt is a $7 part, with about $24 for the tensioner pulley. (And you are a fool if you don’t change pulleys every other belt change.). Valve shims are $2 ea. There (twice or more elsewhere).

But, before we even go there, it is important to determine if this engine is even worth a shit. Here it gets down to very basic tech stuff. And this is where many of our schools have gone astray in their duty to teach… “Let’s start from the very beginning; it’s a very good place to start…”

BEFORE ANYTHING, DO A COMPRESSION CHECK

It is amazing to me how many auto tech courses teach hooking up a diagnostic machine before they teach doing a simple compression check. And it is important that this is done properly. First, the engine must be DEAD COLD AND DRY. That means the car has sat, inactive, for at least 18 hours. This allows all the oil, most particularly that about the cylinder and rings, to drain back to the sump.

Remove ALL the spark plugs. Mark each plug wire’s location with labeled tape or otherwise.

Here you need a compression tester. And, by all means, don’t buy some cheap plastic piece of shit, with a rubber grommet you have to hold in the spark plug hole while cranking. I just bought a very nice, albeit basic, compression tester (#926987) on sale at Harbor Freight. The price: less than $5. Screw the tester into each spark plug hole by hand, finger tight. For each cylinder, crank the engine about 6-10 compression cycles. If you have a remote starter switch, this helps, as you can see when there is no more pressure to be had.

Well, for those of us steeped in the high-compression age of the late ‘60s to early ‘70s, or those new to auto mechanics (who have actually learned the value of a compression check), the ’86 Volvo B230FT might come as something of a puzzle. Because, with only an 8.7 to 1 unboosted compression ration, the motor is doing well to top 125 psi cranking compression.

Going from this number, no cylinder should be under 80 psi, and there shouldn’t be more than a 10% difference between adjacent cylinders.

Well, I’m not going to go into compression testing any further, as there are many very good instructionals on the web. But, as with almost anything else, there is also a whole lot of bunk. But here’s a hint: if what you are reading doesn’t tell you why you started with dead-dry cylinders, it’s likely bunk.

The results of the VEV’s compression test, and more of the general tune n’ troubleshoot, in the next installment.
 
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A blog dedicated to the personal musings of Kevin L. Connors - a pragmatic libertarian, engineer, businessman, and journalist.

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