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Hi Folks,
Went to the garage today for an inspection of my "new" 760. It's an '87 so I figure it must have the B280F V6.
The mechanic whom I've known for years specializes in Volkswagen with a minor in Volvos (his yard is 80% VFolks, 20% Volvos).
So he checks out my new car and comments on its "exceptional" condition, but tells me that this engine is prone to premature camshaft wear. So he opens one of the camshaft covers and inspects it, and we can see that some of the cam lobes show some pitting. This engine was supposedly rebuilt 2 years ago. Is that normal? It also seems that there isn't much oil there (to me anyway): lifting the cover, no oil drips from the side. When asked about the life expectancy, he says it won't die tomorrow, but it won't last forever either.
My question is, is that engine prone to camshaft failure like the older B28F and what could I do to make it last? After the inspection he took it far a spin and thought it ran surprisingly well, and said I should not adjust the valves (the lifters are a bit noisy) as it would wear the camshaft more. He recommended I use an anti friction additive to slow down teh camshaft wear. Basically, at the end of the inspection he was much more positive than at the start and he said it was "definitely worth putting money into"
After a lengthy research on the internet, I am a bit puzzled as what remedial action to take regarding camsahft wear. I hear that engine flushing may clean out the oil passage ways and that it could improve the situation. The engine has been fed synthetic (Castrol 5W50) for almost two years now. Any advice regarding oilo additives? I have a bottle of Wynn's Metaloil lying around...
I'd love to hear your opinions on that matter :¬)
Thanks in advance,
Chris
BTW, I'm told that if the cams lobes are a bit worn, that the valves won't lift properly and the engine may not give its full performance, which could explain my slightly high fuel consumption. There is no carbon buildup (nor any other as a matter of fact) on the tailpipe.
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posted by
someone claiming to be bob
on
Fri Oct 22 16:06 CST 2004 [ RELATED]
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For what it's worth, I have not seen or heard of premature cam wear on any B-280. The timing chains will go first.
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Well if I could post a picture I would, the wear is noticeable on one of the cams at least. Haven't seen all of them, this was a general inspection after all.
Any quick pointers on how to post pictures here?
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posted by
someone claiming to be Chris in Calgary
on
Fri Oct 22 16:35 CST 2004 [ RELATED]
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Just a note that slight pitting of the cam surface does not seem to be the same thing as wear. My 1969 BMW motorcycle has had the same slight pitting on the cam surfaces for over 100,000 miles with no change (I first inspected it at around 40,000 miles.) No explanation, just my experience. Cam lift has not changed since new.
Does seem strange that your cam seems so dry of oil, though.
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the b280's head is designed to avoid just that-camshaft wear. there are pockets in the head to collect oil so as the cam passes through, it collects the oil and throws it towards the rocker arm. the b280 also has a distributor cap on the end of the left head. the b27/28 has it's dist on the back of the right head, behind the intake. makes me wonder what motor it is, or if it's really an 87. good luck, chuck.
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Well it seems confirmed that it IS a B280F.
As for oil, there wasn't a lot under that cover... And the cams appeared to be quite dry. I mean, the parts did not seem coated with oil, but rather "misted" as if they were sprayed with WD-40, not as if they were coated with real oil. On my other engines, the valve cover would always drip substantially when I removed them. Is that because the 5W50? And it's pretty much all brown on the pictures, even though the oil on the dipstick is clean as can be. I'll run the engine with the cover off to check whether oil gets there properly or not. I'm still learning...
In any case, I added a bottle of Wynn's Metaloil I had lying around. Don't take my word for it, it may be the placebo effect, but it felt slightly more powerfull after I added it, and definitely quieter. Hmmm!
Next I'll try a good engine flush...
Thanks for the reply, guy ;¬)
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Hello:
If the build date is post 09/86, then it should be a B280F not a B28F. My understanding is that the B280F did not characteristically suffer from the premature camshaft lobe wear that the B27/B28's did.
If your mechanic had the valve cover off why didn't he adjust the valves (particularly if they were noisy)? It is about as difficult as doing it on an old aircooled VW (in fact the adjusters look very similar) and there are no shims and no hydraulic lifters. The other bank of valves is more difficult because you have to move the AC compressor...
I am a little unsettled by the recommendation to add anti-friction additives... good oil is _the_ preferred anti-friction additive-- if it were mine I'd go with the Mobil 1 10-30 synthetic for high mileage cars that I now run in my 240. The B280Fs originally called for 15-40 oil, which is a diesel oil that has a high level of detergent in it.
With my B280F I would occasionally perform a chemical engine flush prior to oil changes. The bottom end on these motors is virtually bulletproof, and I noted that the oil would stay very clean looking for a long time. I think I would recommend a flush with a high quality product, for example the Amsoil engine flush.
With regard to the engine being rebuilt 2 years ago-- it is hard to know what was actually replaced without seeing an invoice with parts listed. Some "rebuilds" are little more than gasket replacements others are comprehensive rebuilds with many new parts...
Another tidbit about these engines-- they are mostly aluminum and are quite prone to corrosion, especially that caused by dissimilar metals. Proceed carefully when removing bolts from things like the valve covers and the water pump-- they have a bad habit of coming out with the threads attached! Also, get your coolant changed regularly-- this will cut down on internal corrosion, which can be a problem around the cylinder liners.
Good luck!
--
Herb Goltz, London, Ontario, Canada '92 245 w/109K mi
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"If the build date is post 09/86, then it should be a B280F not a B28F. My understanding is that the B280F did not characteristically suffer from the premature camshaft lobe wear that the B27/B28's did."
Well I was not sure because the engine had been replaced TWICE and I thought that possibly, an older engine may have been installed. I have since learned how to recognize the engines: teh B280F supposedly has the distributor in the front while the B28F had it in the back. Besides, the newer engine has the electronic injection system and the jumble of wires and hoses seems to indicate it's pretty much a first generation of its kind. I've never seen messier in terms or engine bay organization!
So based on the location of the distributor, I presume it's a B280F.
"If your mechanic had the valve cover off why didn't he adjust the valves (particularly if they were noisy)? It is about as difficult as doing it on an old aircooled VW (in fact the adjusters look very similar) and there are no shims and no hydraulic lifters. The other bank of valves is more difficult because you have to move the AC compressor..."
Well he said they were not particularly noisy (he's seen much worse) and advised me against it and I understand his reasoning that if the engine is worn, reducing the clearance may increase the possibility of worsening the wear on the cam lobes, considering how scored they are at this time. On one of the lobes you can clearly see the wear, the tip of the lobe is down at least one millimeter and I am not exagerating. There are also visible pits.
My personal opinion is, they could be adjusted, but that will have to be done by feel while the engine is idling, not too difficult to do, I'm very famliar with this rocker design.
"I am a little unsettled by the recommendation to add anti-friction additives... good oil is _the_ preferred anti-friction additive-- if it were mine I'd go with the Mobil 1 10-30 synthetic for high mileage cars that I now run in my 240. The B280Fs originally called for 15-40 oil, which is a diesel oil that has a high level of detergent in it."
Well thank you for the specs, I didn't know it called for such an oil (15W40). I wonder if THAT may not have contributed to the visible wear, as the PO was always running the pedal to the metal, and he was using Castrol Syntec 5W50 and prior to that, regular 10W30. In any case, it's quite brown under there so I know it will require more detergent than normal to get rid of the junk from the oil passages and definitely some more anti friction additive to reduce cam lobe wear.
My mechanic basically recommended an additive package to boost what is already in there, the other alternative being, coming back sooner to have the engine pulled out. Besides, additives have a reason to be: regular oils are designed for regular engines under normal conditions and normal wear.
Yes, they are totally useless on new engines that aren't stressed and are used under normal conditions, just like you don't need vitamins either, good nutrition suplpies all you need.
"With my B280F I would occasionally perform a chemical engine flush prior to oil changes. The bottom end on these motors is virtually bulletproof, and I noted that the oil would stay very clean looking for a long time. I think I would recommend a flush with a high quality product, for example the Amsoil engine flush."
Well I guess that will be next on my list... When it's time for an oil change! It was changed just days before I took possession and I would feel ashamed to drop 6 liters of synthetic for no good reason.
""With regard to the engine being rebuilt 2 years ago-- it is hard to know what was actually replaced without seeing an invoice with parts listed. Some "rebuilds" are little more than gasket replacements others are comprehensive rebuilds with many new parts..."
True! And I did not see the receipt for that either, although it was done at UAP. Mind you, the PO was very lead footed. The reason he gave me for using synthetic: so he could drive at 180 instead of "just" 160 kph!... In any case that engine supposedly cost him $5000...
Did I mention he was a maniac? In any case, he drove it hard, very hard, all the time...
"Another tidbit about these engines-- they are mostly aluminum and are quite prone to corrosion, especially that caused by dissimilar metals. Proceed carefully when removing bolts from things like the valve covers and the water pump-- they have a bad habit of coming out with the threads attached! Also, get your coolant changed regularly-- this will cut down on internal corrosion, which can be a problem around the cylinder liners.
Good luck!
-
Herb Goltz, London, Ontario, Canada '92 245 w/109K mi"
Well thank you very much for your kind reply! :¬)
Chris
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The 5W-50 is likely too viscous: I would stick with a 5-30 synthetic in order to achieve better flow rates at all temperatures.
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How can the 5W50 be too viscous since it starts at 5W when cold?!
Puzzled!
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A 5W-50 oil has two disadvantages: you are likely using Castrol Syntec which is a HVI oil, created from crude stocks into a semi-synthetic that performs like synthetics with one exception: the low-end viscosity is created by adding VI improvers which do not add lubricity. And they wear out. So over time, your 5-50 oil starts acting like a 20-50 oil until you change it.
Second, at temperature it provides high viscosity (resistance to flow), but no appreciably greater film strength or lubricity than a 5-30 synthetic.
See the 700/900 FAQ lube file for more information.
I would use a couple of treatments of AutoRx to clean the internals, followed by regular use of Mobil 1 (or other full synthetic such as Redline) 5-30 oil.
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Good to know about the Syntec! BTW, the PO just had it done juts days prior to the sale: an oil coooler hose had busted so he DROVE to the garage. Apparently no warning lights ever appeared, but the reapir cost him $200 (mostly oil and filter I presume since teh filter wa new when I got the car)
Anyway what sold it was that after he put $500 the week before to replace both fuel pumps it still didn't start reliably so after the oil scare and he got fed up and let it go... for $500, which is less than what he spent the last couple of weeks after he had talked me into adopting the car...
As for Auto-Rx, I'm in Canada and haven't seen the product but at the next oil change I'll definitely use an engine flush.
Thansk for your input!
Chris
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Order by mail from www.auto-rx.com
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posted by
someone claiming to be jrroberson
on
Fri Oct 22 00:13 CST 2004 [ RELATED]
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Best stuff I've ever used is Auto-Rx, the have a web page and is not snake oil.
Good luck
Poolman
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Thanks for your answer - What do you think of internal engine cleaning processes? I've seen one that used a machine that pumped this detergent solution to clean out the internals completely. Although the engine is supposed to be a B280F, I'm still concerned about camshaft lubrication. There was hardly any oil that I could see after we opened the camshaft cover (driver side) and I am more accustomed to seeing parts coated in oil and oil pooling in recesses. No oil dropped when we pulled the cover off.
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I've used the Bilstein Engine Flush process and it appears to work. It pumps hot detergent/oil solution through the oil filter port, back up through all the galleries, and is sucked out through the pan drain plug. You follow with an oil change.
Given you've just dropped six liters of synthetic in the car, try a cleaning additive instead: AutoRX is highly recommended. It's an ester, which is a very good detergent, and is reputed to strip crud out of engines. Pricey but good.
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I forget what the brand of the process was but saw something like that at a Canadian Tire. But they weren't offering the service anymore as they had too little business and were returning the machine. It cost something like $100 or so IIRC. Is that a typical cost? i'd sure love to clean out those oil galeries.
Thanka again for your input, Steve :¬)
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I forget what the brand of the process was but saw something like that at a Canadian Tire. But they weren't offering the service anymore as they had too little business and were returning the machine. It cost something like $100 or so IIRC. Is that a typical cost? i'd sure love to clean out those oil galeries.
Thanka again for your input, Steve :¬)
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