I asked about timing chain oiling perhaps a couple years ago and I know there have been many posts about it since that time but I do not know how to find them.

I finally have a slant 6 torn down for cleaning and to install new gaskets and seals and get it ready to swap into my car. I rebuilt this engine back in 1986 and put 80,000 miles on it before that car rusted away.
Now's my chance to improve timing chain oiling.
Some have mentioned drilling a hole in the front galley plug. What size hole? I am a machinist and we have tiny drills at work. (.015, .020, .025 inch etc). What size hole to I drill? Does this hole get the varnish buildup in it like other internal engine parts get? Or does the full pressure oil flow keep it open?

My factory service manuals upto about 1975 or 76 mention a chamfer on one of the front main bearing inserts that is for timing chain oiling. I do not have an original front main bearing to see what this feature looks like.

Later factory service manuals mention something about an "annular groove" in the front cam bearing that is for timing chain oiling. Again I do not have an original factory example of this feature.

Maybe we need a oil drip guide like on a small block Mopar?

Glad you brought this up. In addition to Craig's questions, has anyone ever had trouble with a "noisy" timing chain on a slant six? I replaced the set in the "race" Duster with a standard replacement set (didn't know a double roller was available at the time). The only problem I've ever had with this motor is a strange, very difficult to describe noise which eminates from the front cover. It sounds like a belt problem, but I've run the motor sans belts and accessories, and the sound is still there. I'm 99.9% sure it is the chain, perhaps from insufficient oil. Sometimes the noise even goes completely away, but it always comes back. Plan is to install a double roller setup and possibly address any oiling issues mentioned above at that time. Thoughts? Anyone else encounter this?

D/W

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If it ain't broke, fix it!

Hey Dennis,
My slants make the same strange noise. This engine I"m working on now had an aftermarket timing set I installed back in 1986 when I rebuilt the engine, well worn after only 80,000 miles. I occasionally cut open my oil filters and always find metal flakes in the filter. I see now it is from the timing gears, they are worn and I can see how the chain pounds on the gear teeth and makes them flake away. Yucky phoey. I have a double roller set I ordered from MP some years ago and that is what is going in.

I think the reason for the nylon on the OEM cam gear is to make it quieter.
I don't understand why they have to do things to make "silent chain" quieter. Am I missing something?

By the way, does anyone know where to find OEM equivalent timing chain and crank gears? I know someone who has about 10-15 NOS original slant 6 cam gears with the nylon outside. I think these OEM sets are better than the aftermarket stock replacement crap they sell us at the local auto parts store.

Interesting to hear... No way I'd put back a nylon tooth gear, though... yuck! Like you, I'm wondering if it's not getting sufficient oil, and the best way to correct.

D/W

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If it ain't broke, fix it!

Can you drill an 0.030 or 0.040 hole in the oil galley plug to oil the chain? Is there a plug and is it in the right position? If so, I would.

Mitch

That is what I'm asking....... What size hole? I do not understand why non of the experts are replying.

Drilling the galley plug would squirt oil at the cam gear and perhaps splash around from there.

I file a champher on the edge of the # 1 main bearing, similar to the old OEM bearings. However I just file from the groove in the bearing to the front edge. That forms a channel to dirrect oil to the chain. I can't post pics. Maybe Doc can post a picture of what I am talking about.

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Charrlie_S
65 Valiant 100 2dr post 170 turbo
66 Valiant Signet 170 nitrous
64 Valiant Signet
64 Valiant 4dr 170
64 Valiant 4dr 225

...say fr'instance that your mains are already long since installed and you have no intention of yanking the motor back down? What then?

D/W

_________________

If it ain't broke, fix it!

I got a timing chain set with my Comp cam and both gears are metal. I don't know if that is what you want. I pulled my timing chain cover off last night and the old set has two metal gears as well. I don't know how old they are.
If you want a double roller, this might interest you.
http://cgi.ebay.com/ebaymotors/ws/eBayI ... gory=33625

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"Nothing in all creation is hidden from God's sight. Everything is uncovered and laid bare before the eyes of Him to whom we must give account."

I saw that one on Ebay. We can buy them cheaper elsewhere.

For about $20 more than the price of that chain, you can get a multi-keyed one from the Cox brothers so you don't have to drill and bush the cam gear to get your cam centerlined....

I would be interested in seeing a pic of the camfer also.

Question though, if you direct some oil to the timing set, would it be mandatory to get an oil slinger for the front seal? (since, like crank bolts, only 10% of the slants got them?)

-D.Idiot

I have been away from the computer for a few days, went to the beach with the family and did other stuff that starts with the letter "S". (Sun, Surf, Sandcastles...)

Anyway.... I always drill a .020 size hole in the front oil gallery plug to spray oil on the chain. Use a larger drill on the backside of the plug to get most of the way thru then poke it thru with the small drill. try to angle the hole to spray right on the chain.

I also use the slinger, more to protect the backside of the front seal from getting a lot of oil thrown at it.
DD

Hey Doug!
I suspected that perhaps you were gone. What about that other "S" word ............. Sunburn?!?

Anyway, studying the location of the plug and cam gear and chain....... a straight through hole would squirt oil straight through the holes in the gear as it turns. The galley plug has such a deep square hole in it that it would be difficult or impossible to get it to squirt at such an agle to be aimed at the chain. What do you use for a plug. Perhaps a Hex head plug from the hardware store would work if there is enough clearance for it behind the cam gear. I will look at that option.
Does this .020" hole stay open with the oil pressure? or does it get that brown coating in it like the big galleys and all the other internal engine parts and plug it self?

Doug, I looked this over and there is no easy way to get the oil to squirt on the chain itself. Am I missing something? The galley plug is aimed right through the holes in the gear (see picture). There is a deep square hole in the plug so no way to drill an angled hole.

even if the oil spray is on the back of the gear set, centrifugal force will fling it to the chain at the edge soaking it liberally