Timing chain tensioner? + new water pump?

Bluemike

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Hi folks, I'm not tech savvy, trying to learn the right way to ask questions and find answers etc and thank you for your patience.
I bought a 1968 Fury three (318, automatic, PS PB)FA STOP (insurance agent told me this???) and I told my wife, "All's I'm gonna do is drive it......then, well.. change the ignition THEN just drive it, and put a 4 barrel on, dual the exhaust...then just drive it....and maybe repaint the engine compartment put better brakes on wood steering floor shift...and then JUST drive it.
Now the engine's 1/2 apart.
My questions are; I'm replacing the timing chain (noticed I have to turn the crank an inch+ before the distributor moves). When I ordered it, the site recommends a timing chain tensioner for another $40, the spending's gotta slow down sometime; I don't plan on spinning this engine past daily driving..should I add the tensioner? Does it help performance?
Years ago I raced enough small blocks without one but wonder if it's a good idea.
Second question; When I started tearing the engine down I noted the thermostat has been gutted, the coolant was black when I took the lower hose off and gonna have the radiator boiled out or simply flushed. It ran fine, no steam out of the exhaust, no bubbles in the radiator etc. Usually when a water pump started leaking was my que to replace it, can the impeller slip or something I'm not aware of with the pump contribute to overheating? I'll of course continue looking for other cooling problems, but once again I really have to draw a line on what to replace ..."while I'm at it" or "just in case. Thank you friends, Have an awesome thanksgiving.

IMG_20221005_225328212.jpg
 
Question 1, No. Never heard of putting a chain tensioner in a 318.

Question 2. Buy a thermostat. I personally like a 160, but a lot of guys like 180 degree thermostats. Use the water pump you have... If it doesn't work out, replace it.
 
Have a look at this thread:

They mention the Mopar P5007709 and also the tensioner for a 3.9L v6 (with rock auto link). I look at both, they seem identical.
 
Yep. I like it. I sold my last classic, 1972 Chrysler wagon; 20 years ago and it's taking me a little bit to go back to thinking old school "If it works leave it alone!".
The other issue(s) I'm hoping to solve, and hoping you have advice on is:
The power steering, typical for some cars of these years, feel like an arcade game, you can turn them with your pinky, have NO road feel. The brakes are the same way (4Xdrum power). You push the pedal an inch and you're bouncing off the dash. The two make quite a combination.
Memory serves me I recall you can shim the pressure relief valve under the high pressure hose in the pump to lessen the POWER POWER POWER steering, you ever heard of someone adding a steering stabilizer to it also?
Be nice if the wheel would center. Yes, it's pending an alignment which string, tape measure and toe boards tell me it's pretty close. All the parts are fairly new.
The power brakes are a different story. Seems to me there used to be a little rubber pad on the booster where the shaft from the master mates up?? Visa versa? Any suggestions making it a little less sensitive? Thank you again, hope you had a Happy Thanksgiving Big John
 
Use a quality double roller chain (like a Cloyes) and you won't need a tensioner. The rubbing blocks on the tensioner are narrow and designed for stock width chains.
 
Please stop the madness with the chain tensioner...is there something in the water???
Use the tensioner- they work, work well, the engines run wayyy better. Rock solid timing. Drill the 4th hole, use a quality double roller chain. Buy the mopar part not the aftermarket part. For those badmouthing the tensioner - how many engines have you built engines with the tensioner and ran the snot out of them? Well we took one road course type engine with 18,000 miles apart for other reasons and did not replace the chain and tensioner. Come on show me the failures, i can't wait to see the carnage and poor assembly mistakes.
 
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This thread is enough to convince me to put one on my '67 Monaco (with rebuilt mid-80's 318) if I ever have the timing cover off.
 
This is interesting. Never saw this being retrofitted, but then again, I haven't been really looking for it either... I've never done much with small blocks.

It makes some sense, and reading through everything posted, it's something that can be done without too much heroics, so I would probably look to do one on the next small block I do (which may be the 273 in my Barracuda). That said, these cars ran a lot of miles before these tensioners were in use, so the question is if you really need to add one for a car that's going to go to Cars and Coffee at the Tasty Freeze once a week in nice weather... If it was something being raced or expected to be driven a couple hundred thousand miles, then yea...

So, I would say that its up to the OP. If he wants to add the tensioner, great, but if he doesn't want to spend the time and money, that's great too.
 
I recognize the value in a tensioner. I recognize the value in fuel injection. I recognize the value in electronic ignition. I recognize the value in a new car.

I love the old cars for reasons that aren't rational. You're never going to make it behave like a 2022 model and frankly I don't know why you'd want to.

Whenever possible, I leave mine as much like it left the factory as possible. Not because I'm a purist or because I'm concerned with what people might say but because I like the old cars because they're old cars.

Replaced a master cylinder today on my '64 Newport and the replacement had a 10mm bolt holding the lid down. Irked me.

If you try to logic it out, there will always be a 'better' part because improvements are always being made for everything from your car to your phone to your house. Personally, I find it more rewarding to adjust me.
 
You're never going to make it behave like a 2022 model and frankly I don't know why you'd want to.
This has been my mantra for a long time...

I do like a little "modernization" if you want to call it that... Radial tires, halogen headlights etc.. Just making it safer and a little easier to drive and maintain, but to each their own...
 
Hi folks, I'm not tech savvy, trying to learn the right way to ask questions and find answers etc and thank you for your patience.
I bought a 1968 Fury three (318, automatic, PS PB)FA STOP (insurance agent told me this???) and I told my wife, "All's I'm gonna do is drive it......then, well.. change the ignition THEN just drive it, and put a 4 barrel on, dual the exhaust...then just drive it....and maybe repaint the engine compartment put better brakes on wood steering floor shift...and then JUST drive it.
Now the engine's 1/2 apart.
My questions are; I'm replacing the timing chain (noticed I have to turn the crank an inch+ before the distributor moves). When I ordered it, the site recommends a timing chain tensioner for another $40, the spending's gotta slow down sometime; I don't plan on spinning this engine past daily driving..should I add the tensioner? Does it help performance?
Years ago I raced enough small blocks without one but wonder if it's a good idea.
Second question; When I started tearing the engine down I noted the thermostat has been gutted, the coolant was black when I took the lower hose off and gonna have the radiator boiled out or simply flushed. It ran fine, no steam out of the exhaust, no bubbles in the radiator etc. Usually when a water pump started leaking was my que to replace it, can the impeller slip or something I'm not aware of with the pump contribute to overheating? I'll of course continue looking for other cooling problems, but once again I really have to draw a line on what to replace ..."while I'm at it" or "just in case. Thank you friends, Have an awesome thanksgiving.

View attachment 568909
There is no right or wrong answer. Here's my 273 build thread. I used a 3.9 V6 tensioner that you can see. Read along or scroll past as you see fit. Like I said before, I used it with a good double roller and it really wasn't necessary with that combination. 273 Build
 
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Please stop the madness with the chain tensioner...is there something in the water???
Use the tensioner- they work, work well, the engines run wayyy better. Rock solid timing. Drill the 4th hole, use a quality double roller chain. Buy the mopar part not the aftermarket part. For those badmouthing the tensioner - how many engines have you built engines with the tensioner and ran the snot out of them? Well we took one road course type engine with 18,000 miles apart for other reasons and did not replace the chain and tensioner. Come on show me the failures, i can't wait to see the carnage and poor assembly mistakes.
I don't see anyone badmouthing the tensioner - 2 guys prior to you simply said it's not necessary. OEM smallblocks built/ran satisfactorily for 30+ years with no tensioner.

Tensioner came along for various internet speculations - due to SB Mopar having a really long chain, to prevent mis-machined cam-bore location causing blocks to be junked at the factory (chain became too loose), to quiet a timing chain rattle on the 3.9 V6 (perhaps due to its odd-fire configuration?).

I suspect it also became important with the Magnum engines, whose sequential EFI required accurate camshaft timing because the cam position sensing was done via the distributor's Hall sensor.

The guy says he's on a budget, there are other things he wants to repair on his car. No harm in folks recommending to not put a tensioner in, or to put that $$ toward an even-better chain. After having a Cloyes Tru-Roller in my hands, I'd buy one of those before putting a tensioner on a lesser chain.
 
Please stop the madness with the chain tensioner...is there something in the water???
Use the tensioner- they work, work well, the engines run wayyy better. Rock solid timing. Drill the 4th hole, use a quality double roller chain. Buy the mopar part not the aftermarket part. For those badmouthing the tensioner - how many engines have you built engines with the tensioner and ran the snot out of them? Well we took one road course type engine with 18,000 miles apart for other reasons and did not replace the chain and tensioner. Come on show me the failures, i can't wait to see the carnage and poor assembly mistakes.
My luck goes....I'm the guy who regrets not spending the extra $50-60 and do stuff like put in a tensioner as long as it's all apart anyway. They sell them on amazon for the 3.9 for $37, I'm going with my gut and buying one.
Are you from the Shawano WI area? I have that same pic I took off the local Wolf river/fox valley facebook page.
 
In the engines designed in the 1950s or so, overhed valve engines in the USA brands of vehicles, the chains were short enough that no tensioner was really needed. Unlike many 1990s-design overhead camshaft engines with LONG timing chains. The earlier timing GEARS were replaced with timing chains for quieter operation (and probably less cost).

Certainly, with time and use, especially after the nylon/cast iron timing sprockets came into use, as the nylon teeth wore down, timing chains could become looser and even loose enough for the chain to "jump" one tooth and cause hard starting. In the case of small block Chevy engines, the timing chain cover was close enough that it could prevent that, but the loose chain could rub that cover and cause additional noise and an oil leak from the hole it rubbed into it.

Aftermarket to the rescue, circa later 1980s . . .
For the harder-core enthusiasts who did not mind the gear whine, "gear drives" became available for certain popular engines. You could heard them at least one block away!
Jessel introduced a belt drive system to replace timing chains. At the time, this was ground-breaking and allowed completely-accurate valve timing. Although it was very recommended that you manually check piston-to-valve clearance! This was before the OEM cam-drive belts came into existence for OHC motors! Not sure of their ultimate durability in OEM engines, but they did well in OEM OHC engines, just replace them as you would repkace aged tires, like every 100K miles or so, ON SCHEDULE.

Almost ALL OHC engines, and some OHV engines use timing chain "tensioner blocks". Unlike the oil-pressure-operated tensioners on OHC engines. Where the tensioner extends when oil pressure is present to physically press on the long side of the timing chain to keep it tight. By observation, almost all of the newer OEM OHC engines use roller timing chains and some soert of tensioner mechanism.

With time, the phenolic tensioner blocks CAN and WILL degrade and crumble. Which can cause OTHER issues, by observation, as those phenolic crumbles migrate to other areas of the engine.

NOT sure if the chain tensioner/containment items really make a difference in ultimate timing chain longevity, but from my own experiences, a Cloyes Plus Roller chain lasted well over 500K miles in my '77 Camaro 305, with NO issues and no detectable need to change the distributor location (due to wear) in that time. No reason why a Chrysler engine would be different, that I know of.

I know that many current aftermarket EFI systems require different distributors (than OEM production) in order to get a clean signal for the EFI computer, but NO requirement for a more accurate cam gear drive system than what came with OR is currently on the engine. Certainly, a Jessel belt drive would not hurt anything there, I suspect.

Your money. Your labor. Your dreams. Let us know how it goes.

Enjoy!
CBODY67
 
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I put the tensioners on both my Fifth Avenues and my Diplomat. No problems yet. I also replaced the water pumps since I was already there and it's a lot easier to swap one out in the garage then on the side of the road. All the research I did leaned towards running one. My main goal was rock steady timing.
 
I put the tensioners on both my Fifth Avenues and my Diplomat. No problems yet. I also replaced the water pumps since I was already there and it's a lot easier to swap one out in the garage then on the side of the road. All the research I did leaned towards running one. My main goal was rock steady timing.

As an impoverished junky family man, I too seek the most cost effective solutions for any repair or improvement I make in our family vehicles, and commend your own thrifty spirit. Having a 383, it never crossed my mind to use a timing chain tensioner, though timing gears were considered about 4 yrs ago. I replaced a still decent old Cloyes with a dual roller set, which smoothed down some jumps in the old damper then.

As Ray Davies put it:

"Cheap is small and not too steep
But best of all cheap is cheap
Circumstance has forced my hand
To be a cut price person in a low budget land .... "
 
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