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I used to own an old VW van. It required regular valve adjustments (spec was every 6,000 miles) because it had solid lifters, and as the valve stems gradually stretched with age the clearances would tighten up. VW switched from solid to hydraulic lifters, at least on US-spec vans, in mid-year 1977, eliminating the need for regular adjustments. Because of this I've always assumed solid lifters were something only used on older cars. I recently bought a used 1994 Honda Civic. I was surprised to discover that this car *also* has solid lifters, and requires valve adjustments as well, though not as often. So now I'm curious. Are there any advantages to solid lifters other than the fact that they're cheaper? Are hydraulic lifters mostly something seen on American cars and cars adapted for the American market, or are they common elsewhere as well? The Honda is also the first overhead cam car I've owned -- is this explained by there being a technical reason why OHC engines can't use hydraulic lifters?
12 responses total.
My volvo doesn't require valve adjustments and is OHC, so I'm pretty sure it has hydraulic lifters. Most motorcycles (and Honda started out as a motorcycle maker) require valve adjustments.
In one word: Simplicity! Solid lifters are simple and therefore more reliable. I have adjusted the lifters on my '68 Opel (OHC), my '86 Nova (OHC), just this weekend on my in-laws '72 R75/5 BMW motorcycle (Pushrod) and will be doing it on my '69 R60US motorcycle (Also pushrod, as part of a total engine rebuild.) Repairing the click, click of a hydraulic lifter gone bad can be expensive. However, they are usually pretty darn reliable these days.
Hmm. Is it really that bad? On the hydraulic lifter-equipped VW vans, I think it was mostly a matter of removing the rocker arms and pushrod, then reaching down in with a magnet-on-a-stick to fish out the lifter. Assembly is the reverse of removal. ;> They did seem to go bad a lot, probably because the oil temperatures on those vans were so high. (Mine had solid lifters, though, so I can't speak from direct experience.) I certainly don't mind doing the job. At least on the Honda I can do it without lying on the ground. ;> I know a friend with an old Civic that has a burned valve on one cylinder, and I can't help but wonder if maybe it was just never adjusted, and eventually stopped seating. This was a really common failure mode on the VWs -- once a valve stops seating, it can no longer get rid of heat.
Guy here at work was quoted $2,500 to have the lifters in his 6 cylinder Montero replaced. The thing has under 60K on it and the dealership could not isolate the noisey one so they were going to replace them all. I think it's a 24 valve engine. He decided to keep driving it the way it was.
With a price like that, it sounds like they have to pull the heads to do it, or something.
Interesting. My parents' Honda Civic died at around 45,000 miles (13 years old, so it wasn't as bad as it sounds) due to cylinder head problems that would have cost more than the car was worth to fix. Would that be related to this?
I doubt it. The head was probably warped, usually from the engine overheating. Once that happens oil and antifreeze intermingle and even get into the cylinders turning it into a steam engine of sorts. antifreeze does not make good lubricant so crank shaft bearings wear really fast and my let loose, if the engine is pushed, often putting a piston rod through the engine's crankcase. These types of failures make for spectacular breakdowns on the freeway ;-)
The other thing that kills Civics is if the timing belt breaks. If that happens the camshaft stops but the crankshaft doesn't, and the pistons smash into whatever valves happen to be open. 45,000 miles would be *way* too early for that, though; the recommendation is to change the belt every 90,000 miles.
The Civic has an interference engine?
Sure does.
That's another thing I like about my Toyota.
Interference engines have advantages, but obviously they won't forgive neglect. (Though the belt change intervals on some of them are quite long. The timing belt on my Honda is supposed to be changed at 90,000 miles, and that's apparently a pretty conservative figure.) That's probably why they're uncommon on American cars -- American cars are engineered with the assumption that many drivers will do absolutely no maintenance, so they're designed to hold up as long as possible under those conditions.
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