Mazda B2000 interference motor?
Wolfie
valves? Should I just install a new belt and try to run it? Or pull
the head and check? TIA Wolfie
Dan--
Get the valves checked. When the timing belt breaks it can cause havoc
with the valves. If you run it without checking the valves you could end
up doing more damage than it probably already has.
--
Regards
Dan
===================================================================
Only way to drive a V8 is WOT!
2000 VX SS V8 (Tiger Mica).
1993 VP Exec wagon V6 (Red)
Don't be beige be exciting. Grow old but don't grow up.
===================================================================
Mark Olson
According to Gates, your 87 B2000 is NOT an interference engine.
I would double check this information from at least one other source
to make sure. If in fact it is not an interference engine, you should
be able to safely replace the belt and start it up without needing
to check the valves.
This PDF file on Gates' website has a list of vehicles that use timing
belts, the recommended replacement intervals, and an asterisk denotes
whether the engine is an interference type or not.
http://www.gates.com/downloads/files/catalogs/tbelt.pdf
Mark
BOB URZ
It tends to be a grease magnet on the front of the motor, so you might
want to
spray it down with degreaser then take it to the car wash and squirt the
front down.
Cover the alternator with a plastic bag when you do this. Get the manual
on it and
make sure the marks line up before you put it back together.
BOB
Don Bruder
wrote:
> This PDF file on Gates' website has a list of vehicles that use timing
> belts, the recommended replacement intervals, and an asterisk denotes
> whether the engine is an interference type or not.
>
> http://www.gates.com/downloads/files/catalogs/tbelt.pdf
>
> Mark
Hey Mark...
They got anything on that site that speaks to whether or not the engine
in a 1976 Mercedes 300D (5-cylinder, 3 liter diesel with timing chain,
not belt) is/isn't an interference engine? If they do, I didn't spot it
on my quick look-see. Suspect, since it's Gates, they probably only
cover belt-timed engines?
I haven't been able to find anything online that gives me a definitive
yes, no, or otherwise, and I've gotten three different answers from
three different mechanics that work on (mostly newer...) Mercedes
products. One says "yep, it definitely is, and if it went around a full
turn before the broken chain bound the crankshaft, you can bet your life
you've got an absolute minimum of three valves and probably a piston
shot. Two will probably be intake, the third will be exhaust, and the
exhaust valve probably went through the piston if you didn't get lucky
and have it just snap off in the cylinder", the second says "nope, just
line up the marks, put a fresh chain on it, and you're good to go", and
the third went "Interference engine? What's that supposed to mean?"
(Needless to say, I don't even bother to ask the third one what time it
is anymore...)
I'd like to avoid having to pull the head on this beast to find out, if
at all possible... Although I can see that no matter what else happens,
I'm going to have to at least drop the engine to do the fix. Bad enough
without throwing in a head R&R as "extra seasoning".
--
Don Bruder - dak...@sonic.net <--- Preferred Email - unmunged
I will choose a path that's clear: I will choose Free Will! - N. Peart
Notice: My former ( dak...@primenet.com / Dak...@aaahawk.com ) addresses are
now defunct. Mail sent to either address WILL NOT BE SEEN.
Mark Olson
>
> In article <3BF50810...@adc.com>, Mark Olson <ols...@tiny.net>
> wrote:
>
> > This PDF file on Gates' website has a list of vehicles that use timing
> > belts, the recommended replacement intervals, and an asterisk denotes
> > whether the engine is an interference type or not.
> >
> > http://www.gates.com/downloads/files/catalogs/tbelt.pdf
> >
> > Mark
>
> Hey Mark...
> They got anything on that site that speaks to whether or not the engine
> in a 1976 Mercedes 300D (5-cylinder, 3 liter diesel with timing chain,
> not belt) is/isn't an interference engine? If they do, I didn't spot it
> on my quick look-see. Suspect, since it's Gates, they probably only
> cover belt-timed engines?
I found this on a Mercedes mailing list archive. I don't know but
I suspect the guy is right, that almost every diesel would be an
interference engine because the compression ratio is so high there
is no other way to do it.
HTH,
Mark
--
http://mblist.mercedes-veterans.com/archive/2001/Jan/mblist_Volume:_1_Number:_3941.txt
"Date: Fri, 26 Jan 2001 09:42:40 -0800 (PST)
From: <deleted for privacy>
Subject: Re: [MBLIST] Why build engines "interference" style
The original poster wrote:
> >What is the advantage??
Definition:
An "interference" engine is one in which the piston at top
dead center will collide with an open valve. In operation
this is prevented by correct timing between the cam and
crankshaft thanks to the timing chain, gears, or belt, in
that the valve never goes fully open when the piston is at
TDC.
The timing is disturbed if the chain (belt, gears) breaks, if
the cam sprocket slips, or if the belt or chain is not
tensioned properly. Sometimes if you rotate an interference
engine backwards it will lock up because the chain slack is on
the wrong side. You'll see warnings about this in some
repair/maintenance manuals.
The advantage is high compression, i.e. very little space
in the combustion chamber when the piston is at TDC. Since
Diesel engines require the highest compression ratio, around
22:1, they are (always?) interference engines."
Don Bruder
wrote:
> I found this on a Mercedes mailing list archive. I don't know but
> I suspect the guy is right, that almost every diesel would be an
> interference engine because the compression ratio is so high there
> is no other way to do it.
Sounds like things may be grim for our hero...
<snippage>
> The advantage is high compression, i.e. very little space
> in the combustion chamber when the piston is at TDC. Since
> Diesel engines require the highest compression ratio, around
> 22:1, they are (always?) interference engines."
It's that "(always?)" that worries me. Rats... I want/need a definitive
answer before I go ripping the head off the beast (and adding another
hundred bucks or so to the project price tag for the new head gasket)
Mayhap I try Mercedes directly again. Didn't get a peep back the first
time, though.
Thanks a bunch for trying!
Terry Hollis
Fit the new belt then do a compression check, if the compression is ok,
there is no damage.
Regards - Terry Hollis, Auckland New Zealand
Wolfie
that puppy up and it runs just fine.That Gates site is great for piece
of mind because my parts guy called his machine shop and they
said,"yep ,that's a interference motor".....To bad I don't have a
compression gauge,maybe I'll get one just for the piece of
mind.Also,now that I cleaned the front of the block and crossmember
which was heavily grease soaked,I noticed fresh oil leaking from out
of the plastic timing belt covers.The old belt was oil soaked but at
147,000 miles I didn't think much of it.So,I have to go back in and
replace the crank seal or that new belt is toast!The second time is
going to be easier because the crank pulley bolt is now alittle
looser(my Craftman 3/8's breaker bar was no match for it.Somehow,I
don't think it's as tight now as the factory setting!!! Wolfie