greg@isrnix.UUCP (Gregory Travis) (12/08/85)
Hello again. I thought I would throw this one out.
How sucessful are engine rebuilds (assume they are done as well as
possible)?
I've heard that a proper engine rebuild can restore an engine
to new or better performance. I've also heard that you can never restore
an engine 100% with a rebuild - things have stressed, warped, etc. (after
100k miles) and that you cannot expect to get the same amount of mileage
out of a rebuilt engine as you got from it when it was new.
My car is beginning to show some oil consumption (more than 1qt every
1200 miles) and at first I thought of dedicating this christmas to
rebuilding it. Now I'm considering only taking off the head to replace the
gasket (it does leak) and having the valves/head machined (new/knurled guides
of course). I have a feeling (from looking down into other engines of it's
type) that most of the oil loss may be from valve leakdown and not ring
wear. All compression specs are at or above the factory specs (I may
have some carbon around the rings to help me along). My major objective
is to recover oil consumption (or lack thereof) with minimal engine
trauma and greatest longevity.
If I recondition the head will the added pressure (from well-sealing valves,
etc.) simply accelerate the wear in the bottom end? Is it silly to do
partial (top end) rebuilds? Am I being penny-wise and pound foolish?
The car? Volvo 145. Engine? B20B Miles? 120,000
Well taken care of. Almost no major mechanical work to this point (head
has never been off).
Will summarize.
--
Gregory R. Travis
Institute for Social Research - Indiana University - Bloomington, In
ihnp4!inuxc!isrnix!greg
{pur-ee,allegra,qusavx}!isrnix!gregrjs@hpfcla.UUCP (12/09/85)
> I've heard that a proper engine rebuild can restore an engine >to new or better performance. I've also heard that you can never restore >an engine 100% with a rebuild - things have stressed, warped, etc. (after >100k miles) and that you cannot expect to get the same amount of mileage >out of a rebuilt engine as you got from it when it was new. Here is an example. A friend of mine bought a 1969 Plymouth Fury (ex new york state trooper car) in 1970. He ran the car until it had approx 120,000 miles on it. He rebuilt the engine (sending it out for the machine work of course) and ran it for about 60,000 more miles (very hard miles I might add). I bought the car at this point and put ~30,000 very hard miles on it. At this point (90,000 miles) the engine was burning about a quart every 225-250 miles. I decided it was time for rebuilding. I rebuilt it and much to my suprise the cylinders STILL didn't need to be rebored (they were only honed on the first rebuild). At this time I decided to go for a little more performance. The 440's (at least in those days) could have their heads milled up to 60 thousandths without any clearance problems. I had mine milled 30 thousandths. I also updated to the electronic ignition system that came in a 1973 440. At this point the engine was much more powerful than it was originally and was running beautifully. The car was not in such great shape however. So I bought a 1973 Plymouth (ex NY state trooper car) and swapped engines. At about 40,000 miles someone unable to control their car on a snowy day hit my front end (causing cosmetic damage only). I sold that car at that time. The person who bought it ran it for 60,000 before selling it. I don't know what happened to it after that. Anyway, my experience has been that a good rebuilding job can restore an engine to at least as good as new. Bob Schneider ihnp4!hpfcla!rjs
kitten@hao.UUCP (12/09/85)
> Hello again. I thought I would throw this one out. > > How sucessful are engine rebuilds (assume they are done as well as > possible)? > > I've heard that a proper engine rebuild can restore an engine > to new or better performance. I've also heard that you can never restore > an engine 100% with a rebuild - things have stressed, warped, etc. (after > 100k miles) and that you cannot expect to get the same amount of mileage > out of a rebuilt engine as you got from it when it was new. > > The car? Volvo 145. Engine? B20B Miles? 120,000 > -- > Gregory R. Travis * Although I didn't do any of the work myself, perhaps my experience will assist you in your decision. The car: 1974 Mustang II Mileage: ~125,000 Date: 1983 Purchased in June, 1980 at ~99,800 miles This was when the block was rebuilt. The head had been rebuilt about a year before, due to several warped valves. They promised me this would cure the carb backfire problem and give me more power (I couldn't understand at the time why FORD had put a 4 banger in when it obviously couldn't handle it) but it didn't. I was working at a FORD dealer, and personally knew the mechanic who did it. My car was the talk of the service department, stories of rings coming out broken, 3/8" of gunk on top of the pistons (which I kept as a momento). To make a long story short, promptly after the rebuild, my tiny car would have camaros and an occational porshe 911 for lunch. Once in third I was hard to beat. Now, at 170,000 miles the car is ready to retire, but more from being moved from Sunny Southern California to Colorado than the engine. Now it misses when cold (like below freezing) and the steering rack is loose (worn bushings).
grr@unirot.UUCP (George Robbins) (12/12/85)
In article <641@isrnix.UUCP> greg@isrnix.UUCP (Gregory Travis) writes: >Hello again. I thought I would throw this one out. > >How sucessful are engine rebuilds (assume they are done as well as >possible)? > [[[ massive omission of details ]]] > Gregory R. Travis The satisfaction you get from a rebuilt engine varies greatly depending on the engine and quality of rebuild job. Something like a Volvo would be as good as new if you are willing to spend the money. Some of the newer econo- motors just don't have room to work from, or tend to fail in ways that aren't worth rebuilding (Vega?). In your case, however, I would advise against considering a rebuild until you get the top end reworked. The chances are that this will solve your problems for another 30-50K miles. If not, the cost is still reasonable compared to a quality rebuild. -- George Robbins uucp: {unirot|tapa}!grr P.O. Box 177 Lincoln U, PA 19352 [Any ideas herein are not responsible for themselves!]
bcking@inmet.UUCP (12/12/85)
** Reface this wine with your sausage ** There's a lot of variability in engine rebuilds. In all cases you will be trading off either your time or someone elses time (read: your money) for one or more benefits. To answer your questions point by point: > How sucessful are engine rebuilds (assume they are done as well as > possible)? > I've heard that a proper engine rebuild can restore an engine > to new or better performance. I've also heard that you can never restore > an engine 100% with a rebuild - things have stressed, warped, etc. (after > 100k miles) and that you cannot expect to get the same amount of mileage > out of a rebuilt engine as you got from it when it was new. An engine rebuild can indeed restore an engine to new or better than original. Any low rent engine rebuild/swap shop can deliver close to new performance for another 30K miles or so. If you want the engine completely worked over it will probably last a whole lot longer than the original did. I don't know about Volvo engines or the going rates in your area, but to get an American V8 rebuilt here in New England will cost anywhere from $800 to $3500. You could spend a whole lot more if your looking for high performance modifications and parts. A cheap rebuild generally involves decarbonizing the head(s), knurling the valve guides, replacing bad valves, new oil seals, new rings, a look at the carb, and a look at the distributor. They never do bearing, rod, or crank work, and if the head needs to be decked they'll try a thicker head gasket instead. These guys guarantee their work for about a month or 1K miles, so they play the odds that no major bottom end failures will pop up in that time. It's a safe bet- unless something is seriously wrong with the engine when they take it down it's not very likely to blow up for a long time. You're buying a whole lot of psychological benefit with a cheap rebuild. The car runs noticably better once it's done, because they only rework the parts which will make the most difference. You feel better when you see your neighbors in the morning and your car isn't choking the county in a blanket of blue fog. And you didn't spend that much money to keep your rig rolling for another few seasons. By contrast, a complete rebuild involves bringing ALL engine tolerances back to their original or better values. Balancing (matching components for optimum fit and uniformity) and blueprinting (optimum assembly) can make the engine last longer than a (typical) new one does and deliver better performance to boot. In addition to checking and replacing all worn parts, a top rate rebuild will aslo include a careful check of the block, head(s) and other major cast parts for cracks, and remachining of the block or head surfaces that need it. > My car is beginning to show some oil consumption (more than 1qt every > 1200 miles) and at first I thought of dedicating this christmas to > rebuilding it. Now I'm considering only taking off the head to replace the > gasket (it does leak) and having the valves/head machined (new/knurled guides > of course). I have a feeling (from looking down into other engines of it's > type) that most of the oil loss may be from valve leakdown and not ring > wear. All compression specs are at or above the factory specs (I may > have some carbon around the rings to help me along). My major objective > is to recover oil consumption (or lack thereof) with minimal engine > trauma and greatest longevity. > If I recondition the head will the added pressure (from well-sealing valves, > etc.) simply accelerate the wear in the bottom end? Is it silly to do > partial (top end) rebuilds? Am I being penny-wise and pound foolish? If you want the cheapest route to keeping the car going for another few thousand miles, I'd recommend just driving it until it really NEEDS work. Then figure out if the rest of the car is worth the money for a rebuild. If you just want to get another 30K or so out of it, you may want to just do the top end. I'd check this out with someone who really knows the pathology of Volvo engines. It's possible that your particular engine wears out the bottom end before the top. This is rare, though. Having the engine rebuilt by a cheap and dirty rebuild shop will yield the same end result. If this car is your baby and you expect to keep it forever, you might want to track down a volvo restoration shop for the rebuild, or for pointers on your engine's peculiarities if you intend to do it yourself. It's a whole lot easier to find both good advice and good shops to do work on American V8s because they've been used for racing for such a long time, but I'm sure it's possible to dig up the same sort of expertise for your Volvo. Good luck. R.M. Mottola (Currently unemployed, but not for long.) (Response posted for me by a friend. This too shall pass.)
levy@ttrdc.UUCP (Daniel R. Levy) (12/14/85)
In article <237@unirot.UUCP>, grr@unirot.UUCP (George Robbins) writes: >Some of the newer econo- >motors just don't have room to work from, or tend to fail in ways that aren't >worth rebuilding (Vega?). Funny you mention Vega. I rebuilt one of those using the iron sleeve kits (actually had machine shop do all the machining, I only disassembled, cleaned, and reassembled the works) and the result isn't all that bad, mechanically (though when I switched to synthetic oil, it started to leak around the front seal--I am kind of suspicious here). It (knock wood) runs quite well, even in the depth of Chicago winter such as the teens and twenties below zero. Now, opinions about the rest of the Vega may differ :-) but the engine part can be a fairly tough machine, especially when the original aluminum-silicon matrix cylinders (technically a nice idea, but when a bit of dirt gets in or there is a coolant escape with resultant overheating, it quickly loses its charm) have been sleeved. Comments on sleeved Vega engines, anyone else? >-- >George Robbins uucp: {unirot|tapa}!grr >P.O. Box 177 >Lincoln U, PA 19352 [Any ideas herein are not responsible for themselves!] -- ------------------------------- Disclaimer: The views contained herein are | dan levy | yvel nad | my own and are not at all those of my em- | an engihacker @ | ployer or the administrator of any computer | at&t computer systems division | upon which I may hack. | skokie, illinois | -------------------------------- Path: ..!ihnp4!ttrdc!levy
hakanson@orstcs.UUCP (hakanson) (12/19/85)
<yum!>
Oh boy, Vegas! My brother bought a '72 Vega GT with a sleeved
engine. The work had just been done and it ran terribly,
but he paid $700 for it, had a carburetor job done on it,
and it ran great after that. Surprisingly quick car.
My brother thought he could use some more power and spent some
bucks on a header and a single side-draft Weber carb & manifold.
That didn't breath too well (the Vega is a low RPM engine) until
he put in a different cam that was set up for low and midrange power.
Adjustable shocks, wide wheels and tires, a couple of paint jobs,
and new upholstery/carpeting have made it into a very nice car,
which has lasted for 6 or 7 years. He finally totalled it by
hitting a deer, and it's sitting in my parents' back yard. If
anyone is interested in buying a Vega with some rather exotic
parts in it, let me know.
All in all, it was still a Vega. Even when new they would rattle
for ten minutes after crossing railroad tracks. The engine was
never designed to be sleeved, and the cylinders probably suffered
from cooling problems. My brother put new rings in the thing last
summer and the sleeves were (though not scored) wallowed out in the
middle so badly that it should have been rebored. The GT's had
posi-track rear ends with a ratio of about 3.6, so they were quick.
When the rear end went out after a few years, the posi was too
expensive to find, so he replaced it with one from an automatic,
which was so high geared that the engine would turn about 2000 RPM
at 60 MPH. It was no longer as quick, but would still blow away any
Vega that hadn't had a small-block V8 added to it. Still, I'd have
to say the car was worth rebuilding.
He replaced the car with a '69 or '70 Volvo (145, I think). It has
the B20B engine (dual Strombergs) with a thick head gasket (newly
rebuilt) and alcohol injection to cure pinging. (These things have
disk brakes on four wheels, for crying out loud!) He promptly went
out and got some really nice wheels and tires for it. Some people
never change, I guess.
Marion Hakanson CSnet: hakanson%oregon-state@csnet-relay
UUCP : {hp-pcd,tektronix}!orstcs!hakanson