Timing chain slack

How many degrees of chain slack is acceptable before chucking the thing and installing a new one?

Can excess slack cause idle issues?

What other symptoms would you notice with excess slack?

Mine has 10 degrees.

The factory has a ludicris amount of link chain slack allowed, about 1/2".

The resultant 10 degrees is typical, and why all Ford sixes idle and run on and off the throttle so bad. It also is a risk for conrod to camshaft contact, which in some cases, can take an engine "out".

Ford Australia used a variation of the double row chain from the Austin A series 1275 GT and Cooper S 1097/1275 engines for cross flow Fords.

That is what Vintage Inlines sell. Well worth it.

Thanks for the info. If 10 degrees equals 1/2 inch and that is factory spec. then I think I'll let it be for now. The engine is coming out later this winter for a rear main seal replacement and a new cam, lifters and adjustable rockers, and the timing chain was on the list of might as well.

don't 4get the earlier timing set (what wuz it? '71 & lower?).
Only place I found it wuz NAPA (outta the manufacturer in lower midwest).
The prt #s round here somewhere. It's 'pre-smog' so has some "built in advance".
Degree it wid dat new cam!

Howdy Charlie and All:

Chad's advice applies to later 250 sixes. Not to 200 engines.

Did you check your current amount of chain slack by rotating the crank and watching for the valves to start to move?

I like your plan. I'd sure recommend a set with a double roller timing chain. It will cost more but be worth it in the long run. Your choice.

Adios, David

Hello David,

I checked it as you described, but I watched the rotor on the distributor. As soon as I saw the slightest bit of movement I stopped and checked the timing marks. I performed the procedure three times and the result was the same each time. The timing mark moved from TDC to 10 degrees advanced.

I'm glad you like my plan. I got the idea out of some book...

Charlie

Time for a double roller timing chain. Very good investment.

hey gang....I was thinking I might need to replace my timing chain until I read this post. I have at least 10 degrees of movement before the rotor moves from top dead center. How much is normal... do I need to change it?

that much slop is already affecting the engine performance. If you have the oil pan off now it would be a good idea to put in a fresh chain and gears while it’s opened up. Good luck

I was replacing my oil pan gaskets the other day and mine was super stretched too. I ordered a roller replacement, but am in same situation and may wait until winter.

I’m trying to figure out what parts I will need. There is some talk of an improved timing chain (double roller)? How important is this? Where would I get one? Should I replace the gears with the chain? I also understand that I should replace the front seal at the same time. Any advice is appreciated

The double rollers won't stretch like the regular ones. Much beefier. I ordered mine from Matt Cox at Vintage Inlines. I also ordered a full gasket kit since i have a bunch of work coming up, but you'll want a gasket. https://www.vintageinlines.com/product-page/dual-roller-timing-chain-set-170-200ci I also ordered a high-volume water pump since I am there and mine is showing signs of leaking.

The chain and sprockets wear together and should be replaced all together...If you get the double roller, do not use the oil slinger if you have one , it is not needed and will clash.

escaper said:

The double rollers won't stretch like the regular ones. Much beefier. I ordered mine from Matt Cox at Vintage Inlines. I also ordered a full gasket kit since i have a bunch of work coming up, but you'll want a gasket. https://www.vintageinlines.com/product-page/dual-roller-timing-chain-set-170-200ci I also ordered a high-volume water pump since I am there and mine is showing signs of leaking.

Click to expand...

I am looking at buying a water pump as well....Where do you purchase a "high volume water pump." I am guessing that this helps keep the engine cooler? Right?

SAme site. I thought I would give this one a try to help with cooling. No idea if it would be better. https://www.vintageinlines.com/product-page/high-flow-water-pump-144-200-cubic-inch

From what I remember from my research is that if you have a stock engine a double roller is not really required. When I replaced mine I just did a stock replacement. I would tend to have the same philosophy with the oil and water pump if you are running a stock engine and don't have any oil or over-heating issues.

Required? No, but as slack as mine is, why take the chance?

I understand a small increase is not harmful or real helpful. Stock is fine: Some here suggest the GMB pump. Heres 1 for the 289, look it up for ur motor:
cavitation would B a concern.