'93 Grand Voyager knocking

I have a '93 Grand Voyager with about 146k miles on it. It's developed
a terrible loud engine knock that is progressing. When it started
months ago, it was only when the engine got to normal temp but now it's
from the time you start it up and getting louder all the time. It
sounds like a diesel going down the road. Could it be a rod or maybe
an oil pump? It still runs great smooth with no loss of power.

Thanks,
syd

 

I'm no mechanic but I had the same problem and it turned out to be a
lifter hanging up. The mechanic had to loosen it up, take it out and
put a new one in. You may want to try a high detergent additive that
treats sticky lifters first. I put a bottle of CD-2 in at every oil
change.

 

I'm no mechanic but I had the same problem and it turned out to be a
lifter hanging up. The mechanic had to loosen it up, take it out and
put a new one in. You may want to try a high detergent additive that
treats sticky lifters first. I put a bottle of CD-2 in at every oil
change.

 

That sounds like an easy fix! Did it continue to get louder with time?

 

Assuming you change oil at reasonable intervals and use a good quality
oil, and assuming your engine isn't a "sludge monster," I think you're
overreacting by using CD-2 that much. The detergency in modern oils
is high enough to not need CD-2, like you did in the old MS days.
However, CD-2 can do things like unstick varnished lifters and stuck
rings in extreme cases.

My father-in-law's a big talker, little doer (typical corporate
manager type) and let his Mazda pickup go 20K between oil changes,
with the result being the same thing...a stuck hydraulic cam follower
that was rapping like mad. I excoriated him for being so lax on
maintenance, changed the oil and filter (the filter shell weighed a
TON!) and added a bottle of CD-2. The follower shut up after about a
week, but the sludge and varnish inside the engine was left pretty
much intact. I told him he needed to drop the pan and clean up the
valve train, and he ignored the advice. Predictably, he blew it up
with a plugged oil screen about six months later.

 

heads up, people- this "desertbob" is the same guy that actually drives
a 1978 Honda- he doesn't even know his wrench sizes- the LAST thing you
want to do, is follow or read his tech advice- he just got done
completely disassembling a 318 motor, when all it needed was a
thermostat