Caravan '89 3.0 Auto+OD, Loud rattling Noise from Engine

HI Guys,
Hope to get some help with my 1989 Caravan 3.0 Mitsubishi, Automatic
with overdrive(3-4 speed? P-R-N-Overdrive-Drive-L). Makes a rattling
noise.

I went for a camping trip, about 300Km away. It was fine all the way,
ate a little oil, but i refilled to proper level. On the way back,
somewhere after the last stop ~100Km away from end, on the trafic
lights noticed/heard this bad noise from engine when reached the
city(so at the end really).

It happenes at all revs, mostly between 1-2KRPM, i don't think it is
the transmission, even at park when reved it makes that rattling noise.
I'm pritty sure it is from the engine, possibly the back/passanger side
of the engine.
To describe the noise: it sounds like a bad mufler(you can hear the
combustion intervals), somewhat metalic, low frequency not high pitch,
resonating with revs to the point of ear pluging like in a danceclub
(althought i don't feel like dancing).

I was thinking it might be the timing chain/components OR the
valves/lifters/etc OR Camshaft/Driveshaft/rod bearings.

To bring you up to speed, i had this van for ~2months, it had 282K Km
on it now 284K, rebuilt(somewhat don't have much supporting paperwork
on what was done) engine and transmision at about 200K. When i got it
it had a rusted tiny hole in the oil pan(i replaced) and it had a
rattle onece in a while, which went away after i serviced the van when
i got it(oil & filter & pan, rear pads and drums, drive belt, air
filter, spark plugs, trans oil, removed the dead AC and all components
and other body parts like chrome bumpers rear gate etc) all in all this
van had cost me a total of CND$900(price, parts and registration). I
had another 1989 Caravan 4 cylinder that the trans had died and the
engine was eating oil 1L/100km, it is at the junkers now after 250Kkm,
all the good parts are on this van now.

so what you guys think is wrong with it. Please i need help, don't mind
doing it myself, i'm thinking of going to my old mechanic, which i
didn't see ever since i started doing my own work on the 3-4 cars in
the family.

thanks in a dvance
Ilia

 

Could also be a rod knock. Take it to your old mechanic, ask him,
it is almost certain to be more expensive to pay someone to fix
than the van is worth.

Ted

 

thanks for the reply, sorry i posted this question in the dodge group
aswell

well you know how i mentioned this noise sounds like a bad mufler, well

cuz it is.
Went to my mechanic, he helped point out that the noise is from the
exhaust pipe, his words were "the cat converter guts have colapsed and
all that shit hit the mufler"
that's why i hear this low frequency mufler noise at about 1.5KRPM.

Now this brings another question to my mind.
Can i stick any cat converter and mufler in there, the bigger the
better right? I can weld the pipes with my dad, so i'm thinking i go to

junker and get my hands dirty.


Do you guys know if anything other than the pipe diameter and the shape

of the exhaust/cat matters(so as long as it fits and was made for a
large engine like mine V6 it should be ok, right?)?


thanks
Ilia