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Rachet style Chain tensioners

2253 Views 51 Replies 6 Participants Last post by  eschaider
Hey Ed--- I did get my chrome- moly tubing to create the spacers to eliminate the rachets on my tensioners. I finally got a local machinist to cut it to the 0.200 length. In the interim I had contacted Tim Elchhorn from MPR in Boyton Beach to see how he addresses this with his engine builds. He advised me as long as the rachet does not extend out from the top more than 7/8th's of an inch the rachet can be removed and no spacers are necessary. He says the spacers can be more disasterous than the rachets in snapping chains and has seen this first hand at his shop. It would be great if some others would chime in on this -that have done this modification and race a bit with a two step. I want to button up my engine and get it back in but now I'm wondering which direction I should go. Life can be a conundrum for sure----Thanks


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I just experienced both secondary chains breaking and my intake cam's seizing up. I don't want a repeat with my new heads and engine. Where can I see and read more on this tensioner mod? I will surely purchase the additive. I believe in some and not others. Never heard of this so I'll give it a shot.

Thanks
Dave
I'm an idiot. Tech Table of Contents under the 96-98 cobra page? I don't see an "Engine" section unless I'm in the totally wrong forum.
And there it is. Time to read. I think this is valid. I've seen lots of people with this problem and it's been mostly assumed that the heads take alot of oil and they starve the pan and then the cams seize, breaking the chains. This sounds more viable. Thanks for the help!
Got it. I saw a set of those for sale somewhere and wondered what they did. Do you make them? What would a set cost me?
I have the cast ones from a 94 Mark VIII engine (my shortblock is from there). I'll see if we have any of that tubing in our metal cage. Thanks!!

Dave
We have a nice lathe at work and I have access to a lot of metal so I'll check tomorrow. Should I just remove the ratchet arm all together? Then I don't have to grind anything and guess 3 or 4 teeth. Thanks for the link guys. I don't think I'd ever have known about this. I'm going to get my crank from being turned after this problem and was assuming it was oil starvation or something. I built a 7 Qt pan and filter setup and was planning on the cobra pickup and pump for it. This could have easily happened again to me if the tensioners were my problem. With the symptoms and how it happens, this sounds valid. Thanks again!!

Dave
I have 2 sets of the cast iron tensioners so I'm going to go ahead and make the spacers for all 4. I'm planning another build with some DC heads I found. I do have the crossover mod done. I also am going to have billet gears. I'm going to look up the reverse tensioner mod. I saw MMR had a set with it flipped. I degreed my cams in when I first built it and they were around 3 and 6 degrees off between the cams. That added to the potential extra 6 would surely explain the differences in the stock setups and the freak engines. Thanks!
My engine is in a 63 fairlane. Tight but works!
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Well, I do need the entire timing chains and gear but This is an awesome option. I favorited that site and will be getting the dowels as well. You guys are a wealth of knowledge on these engines. I just got my crank back today and all my bearings are on order. I can't wait to start putting this thing back together and see if I can tell a difference in the power from the timing. Peace of mind will surely be there though this time.
Ack! You're killing me smalls!!! I just ordered a foot of the tubing for my own. No biggie. I have 2 engines I'm going to do it for on my own and a friend who has one I'll make some for as well. Good for you though! Good luck with the rest of the build! I just finished getting the short block together. Ordering my Cobra flipped tensioner soon and will have it together in no time.
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So, I got my tensioners off, spacers made, and then started to put them together. Uhoh! I have different tensioners than what I've seen all over. Consensus was to get a new ford set so I did and the spacers work. I'm leaving the ratchet stop out. I know they say for racing only but if this falls apart, I'm not thinking this one piece is going to be want causes a catastrophic issue. That'll happen before. So, pics of my tensioners (that I find no part number or likeness anywhere on the net) and the new ones with spacers installed. I really think they could be slightly less than 0.2" but that's me. I'll go with what's recommended. Thinking though, Wouldn't it be better if the check ball was removed insode the tensioner as well so it could surely collapse onto the spacer stop to ensure it doesn't stay pumped or do they bleed down anyways?

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Exactly. I do see how the spacer holds the tensioner to a point just under tension of the guide so it'll do fine. Those old ones I have would still work but I played around with them and I ground 4 teeth off the ratchet part. They actually need 5 off to keep them within the limits of the new tensioners. I bet they were the first iteration and they had limited quantities before they went to the new style. I left the ball valves in as built. I think they have to bleed down at some point but it is interesting to ponder. The ratchets were my problem. With the added chain slack at the higher RPM shifting, they would ratchet out another tooth and then not go back in. Then the cams were too tight on the startups we did on the dyno. We'll see how this setup does.
Well that explains the difference. The old style I have are identical in every way possible. Maybe that's the reason for the change to the newer style.
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