The solution to chain rattle

[dylanbike1]

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[altavant]

Scoured cylinder walls are attributed mainly due to inadequate/improper warm up and infrequent oil changes (old oil obviously isn't going to lubricate and cool as efficiently etc).

Timing chain issues are attributed mainly to lack of oil pressure at initial start up in the timing chain guides that add pressure to hold the chains in place. Poor OCI add to this problem as the oil breaks down and doesn't pressurize in the guide as well/as quick.
So when the engine starts and the guide isn't tightly pressed against the guide (due to lack of oil pressure since the engine isn't on - which is why cold starts is when the symptom is most prevalent), the chain can "slap" agains the guide. This quick slap adds to the deterioration of the guide and guide mechanism. Eventually they fail all together and other parts can often go with it as that stress is then applied additional throughout the system.

Personally I don't know enough about the problem to say that this is an adequate solution or not. But it certainly is an interesting approach and appears to address the main problem which leads to further issues down the road. Obviously if a guide is already in poor shape, the damage is done. But anything to pressurize the system temporarily before engine start seems like it would be a very beneficial step.

So what if...assuming OCI & oil itself is good...some whiz bang engineer/hacker programs the starter motor/startup sequence to start with engagement of the starter motor - to a slow crank of the motor - until any possible chain slap/lack of tension is eliminated - then continue to normal starter turnover and ingition sequence? ..a few extra seconds at start up..save a few grand later..??

[Diesel_A4]

Is this gonna be a safe fix even if the car has already been rattling for some time? Or is this gonna he mainly to do before it starts to prevent it from starting?

[dparm]

Is this gonna be a safe fix even if the car has already been rattling for some time? Or is this gonna he mainly to do before it starts to prevent it from starting?

It would slow the rate of degradation, though once things are broken it can't magically fix them.

[Ali]

Am talking to a vendor about a full kit with the 1qt accumulator, electric valve and t-fitting install kit as a complete package. Sounded like he could do pretty good on price, also asked if there would be additional discount if we could get a group buy or multiple orders. Will post once I get some info back.

[howsyouraspen]

Am talking to a vendor about a full kit with the 1qt accumulator, electric valve and t-fitting install kit as a complete package. Sounded like he could do pretty good on price, also asked if there would be additional discount if we could get a group buy or multiple orders. Will post once I get some info back.

Would this be with the same Accusump unit or a different brand? I know Moroso has one too. Also noticed the 2qt size said it's suitable for V6-V8's? Is the 1qt enough?

[Ali]

Would this be with the same Accusump unit or a different brand? I know Moroso has one too. Also noticed the 2qt size said it's suitable for V6-V8's? Is the 1qt enough?

Yes, accusump unit. Saw Moroso but cost differential seems to be marginal. For just startup I would think the 1qt would be fine but he also has the other sizes so could probably make it an option if you wanted larger. OP seems to have had good enough results with the 1qt and and for ease of positioning a smaller unit I will probably get the 1qt.

[0000 V8]

Think I could mount this in the rear with a longer hose? I didnt see a hose longer than 6 ft

[Ali]

Think I could mount this in the rear with a longer hose? I didnt see a hose longer than 6 ft

not sure on this, it seems thats all they offer, maybe you have to keep it short to retain propper pressure.

[Ali]

So here is what the guy came back with:

All Canton equipment:

1Qt Accumulator, Electric Valve, T-fitting install kit and mounting clamps.
5 orders: $340 each + shipping (e.g. shipping to my house was around $30 CA to CO)
10 orders: $320 each + shipping

Same as above with 2Qt accumulator:
5 orders: $350 each + shipping
10 orders: $330 each + shipping

Not sure what the group buy process etc is but if we get enough interest hopefully someone can help me out with the particular or who I need to clear this with before posting the companies info as I don't want to step on any toes here. Either way I will probably get a kit regardless as their normal pricing is not horrible either.

[ilko]

Those prices aren't bad! Thanks for gathering this info and sharing!

[Ali]

Those prices aren't bad! Thanks for gathering this info and sharing!

No problem, theoretically this just seems like a good idea and if it stops my occational chain rattle at startup its a small price to pay.

[Diesel_A4]

Im just honestly curious as to if this will save me from dropping 5K to fix it all being I have had the death rattle for a couple months, if it will save me from that...im in!

[TEB]

*Tracks Thread*

[MattboyR32]

Put me down for a 2qt

[kelseysautobody]

Even if it doesn't help the long term health of the motor for that price I'm in. Hell I'd pay that much to get rid of an interior rattle that I haven't been able to locate for the last year.

[Ali]

nice were already pretty close to the first price break, I guess starting a list would be the next step:

1. Ali
2. MattboyR32
3. kelseysautobody

Please reply and add youself into the list if interested. I called and spoke with him just to double check everthing and said I would contact him in a week or so depending how interest builds.

[SeKKeY]

interested, but i wanna see the install

[0000 V8]

Ali- Are those prices based on just the regular electric unit KIT shown here? https://www.cantonracingproducts.com...ion&key=24-270

Is thiss the proper unit or do we need one of the other electric kits with the rate PSI. Anyone know what PSI we need?

[btroop]

interested, but i wanna see the install

what he said.

[0000 V8]

OP- which electric unit do you have? How long do you need to wait to start the car after the unit is engaged?

[0000 V8]

[QUOTE=Ali;7586730]nice were already pretty close to the first price break, I guess starting a list would be the next step:

1. Ali
2. MattboyR32
3. kelseysautobody
4. 0000 V8

[\QUOTE]

[Ali]

interested, but i wanna see the install

As do I. There is really only two ways to hook these up, an adapter at the oil filter which wont work for ours as it has to be a more traditional screw on type or a with a t-fitting after the oil cooler. Am assuming this is the route the OP went but would love to hear how he did it even if we have to wait for pics etc till he gets back.

Ali- Are those prices based on just the regular electric unit KIT shown here? https://www.cantonracingproducts.com...ion&key=24-270

Is thiss the proper unit or do we need one of the other electric kits with the rate PSI. Anyone know what PSI we need?

Yes, that is the valve I selected.

From what I can tell just for priming at startup this should be more than enough as the rest seem to be race applications.

However if you want a stronger one the deal is we get 10% off with 5 orders and 15% or with 10. You can mix in the higher rated valve or different size accumulator as you see fit.

OP I understand your not at home and cant do a full write-up but any details you can share prior to the full version would be appreciated.

[0000 V8]

OP I understand your not at home and cant do a full write-up but any details you can share prior to the full version would be appreciated.

X2

[peterk81]

I'm in for the 2qt if install kit is complete. Also, does the install kit include stainless lines?

[Latosa]

good post I was refering to this over here !I'm interested on the end result since I have not be able to jump at it . been busy at work too.

http://www.audizine.com/forum/showth...-100-000/page9

[Ali]

I'm in for the 2qt if install kit is complete. Also, does the install kit include stainless lines?

It does, the install kit part number is 24-800, the valve is 24-270, the clamps are 24-240 and the accumulator 1QT is 24-046, 2QT is 24-026 for folks that want to look it up. I kind of pieced this togehter so anyone thinks anything should be changed out please chime in.

[0000 V8]

Anyone know the oil pressure for our motors (in PSI)? Id be interested in the race valves (if anyone thinks its worth it) but would want to make sure Im getting the proper unit for the application.

[LJH]

So what if...assuming OCI & oil itself is good...some whiz bang engineer/hacker programs the starter motor/startup sequence to start with engagement of the starter motor - to a slow crank of the motor - until any possible chain slap/lack of tension is eliminated - then continue to normal starter turnover and ingition sequence? ..a few extra seconds at start up..save a few grand later..??

This is what I am curious about...I am basically doing this but manually. I usually do two 1-2 second cranks and then on the third crank over I let her start. Interesting idea having the ECU control the period of time before you get a spark.

Cheers,
Jim

[Ali]

This is what I am curious about...I am basically doing this but manually. I usually do two 1-2 second cranks and then on the third crank over I let her start. Interesting idea having the ECU control the period of time before you get a spark.

Cheers,
Jim

With the starter cranking at a slower rate so the car wont actually start would the chain still not be moving and hitting just at a slower rate till pressure builds up in the tensioner? May not be as bad as the full on slap once turned over but I would think it would still be making contact.

[LJH]

With the starter cranking at a slower rate so the car wont actually start would the chain still not be moving and hitting just at a slower rate till pressure builds up in the tensioner? May not be as bad as the full on slap once turned over but I would think it would still be making contact.

I see what you are saying....you are asking if you could get the starter motor to turn slower then it normally does. I am not sure that is terribly feasible as you would have to include some sort of electronic speed control to slow the starter down. With that being said I am not sure how fast the starter turns the motor but I know when our car has been sitting for extended periods (1 week +) I do the two short cranks without firing the motor and then on start up there is no chain rattle because the starter has turned the motor enough to bring the oil pressure up and tension the guides.

Cheers,
Jim

[Ali]

I see what you are saying....you are asking if you could get the starter motor to turn slower then it normally does. I am not sure that is terribly feasible as you would have to include some sort of electronic speed control to slow the starter down. With that being said I am not sure how fast the starter turns the motor but I know when our car has been sitting for extended periods (1 week +) I do the two short cranks without firing the motor and then on start up there is no chain rattle because the starter has turned the motor enough to bring the oil pressure up and tension the guides.

Cheers,
Jim

Sorry, didnt state it correctly. What I was saying is the way you are doing it with two short cranks is probably still causing the chain to hit but just very slowly/lightly compared to just starting it without doing the short cranks. So its still making contact till pressure builds up but is not as violent as just starting it without the short cranks.

The accumulator method would build the pressure before anything moves so there should be no contact at all.

I could be wrong, all theory in my head at this point.

[LJH]

Sorry, didnt state it correctly. What I was saying is the way you are doing it with two short cranks is probably still causing the chain to hit but just very slowly/lightly compared to just starting it without doing the short cranks. So its still making contact till pressure builds up but is not as violent as just starting it without the short cranks.

Copy that....we are on the same page. My thoughts are the same as yours, the motor is spinning a lot slower, how much slower I do not know, on the motor then when it fires. My thought is that this is more gentle on the guides then just firing her up.

Cheers,
Jim

[ilko]

I'd like to note that cranking the motor for a second or two without starting it will not build up oil pressure to a significant enough level.

I have an older air-cooled 911 and that car came with an oil pressure gauge from the factory. At idle the pressure is between 2-3 bar, and under load it's around 4.5-5 bar. Sometimes if I haven't used the car for a few weeks I like to crank it with the fuel pump relay out in order to build oil pressure and prevent cylinder scoring. 1-2 seconds of cranking doesn't do anything. You need to crank for a good 5 seconds in order to see the needle move past the 2 bar mark. At that point I am comfortable putting the fuel pump relay back in and starting the car. Just FYI.

And I'd be very interested in purchasing one of the Accusump units through the group buy but would first like to see how exactly it's installed.

[mbgt72]

I don't think the speed of the starter is something that can be controlled. It's an on off system based on electrical current being provided (hence "jumping" the starter cranks at the same speed), not ECU control. And supplying less than ideal current is probably just going to strain the unit and burn it out faster as it strains to turn the motor. Staters are doing a pretty big job out of pretty small components. And they're not a part I like to put any more strain on than intended or necessary.

Also, how does one "let it crank several times before starting". . . . Are you just bumping the key on and then off real quick to prevent the motor from actually starting? I can't imagine that's very beneficial for the rest of the system as it sounds almost like shorting power out of it repeatedly.

[b spot]

In for a 1qt

1. Ali
2. MattboyR32
3. kelseysautobody
4. 0000 V8
5. b spot (1qt)

[LJH]

I'd like to note that cranking the motor for a second or two without starting it will not build up oil pressure to a significant enough level.

I have an older air-cooled 911 and that car came with an oil pressure gauge from the factory. At idle the pressure is between 2-3 bar, and under load it's around 4.5-5 bar. Sometimes if I haven't used the car for a few weeks I like to crank it with the fuel pump relay out in order to build oil pressure and prevent cylinder scoring. 1-2 seconds of cranking doesn't do anything. You need to crank for a good 5 seconds in order to see the needle move past the 2 bar mark. At that point I am comfortable putting the fuel pump relay back in and starting the car. Just FYI.

And I'd be very interested in purchasing one of the Accusump units through the group buy but would first like to see how exactly it's installed.

Ilko,
while cranking the motor with the starter does not produce running oil pressure it does make a difference on my car. My car does rattle very slightly on initial start up after sitting for a week +, more so when it is cold out (>45*) and the oil is getting close to its 5K mile OCI, but I have taken to giving it a couple cranks before starting about 18 months ago and as long as I do that I do not get any rattle at all. Back in March our S4 was not started for 3 weeks, when it came to start it for the first time it was in the mid 20's and after two short cranks she started without a hint of rattle. Now YMMV but I am sticking with this procedure as it works for me.....but this may be because our car does not show anywhere near the amount of rattle that people talk about on here, in fact during the summer and up to about 4K miles into the OCI I do not get any rattle at all.

Cheers,
Jim

[LJH]

Also, how does one "let it crank several times before starting". . . . Are you just bumping the key on and then off real quick to prevent the motor from actually starting? I can't imagine that's very beneficial for the rest of the system as it sounds almost like shorting power out of it repeatedly.

Well...you are not shorting anything...you are just supplying power and then turning the power off. Yes, you are getting an amp spike initially because the motor is starting up but nothing like a dead short. While this may tax the starter motor a bit more then normal I am not all that concerned for the fact that I just installed a new starter last fall (infamous solenoid issue) and our car is not a daily driver meaning our starter is still seeing many less cycles then a normal daily drive car...I do this procedure once a week when I pull it out of the garage on Saturday morning and after that it does not rattle for the rest of the weekend on normal start up. Also the starter is $165.00 and 3 hours worth of work compared to $3500 in parts and having to remove the engine for chain guides.

Cheers,
Jim

[04v8s4]

Woah woah woah. You guys have no idea what you are talking about!!! You are all guessing as to the cause of tensioner failures. What makes you think it's a hydraulic issue?!? I'd be much more inclined to bet big money on material fatigue of the actual guides. They are an injection molded plastic part that's subjected to thermal cycling and mechanical fatigue. Plastic mechanical properties degrade over time with thermal cycling and become more brittle. They also see cyclic loading from the chain. So what makes you guys think an accumulator will magically solve a fatigue issue!?!? Jesus crist guys....everyone jump off the bridge now!!

You hear chain slap/rattle because the chain spins up to 1300 rpm immediately after start up with no tension on it...then quickly settles back down to idle. Wtf....

[LJH]

Woah woah woah. You guys have no idea what you are talking about!!! You are all guessing as to the cause of tensioner failures. What makes you think it's a hydraulic issue?!? I'd be much more inclined to bet big money on material fatigue of the actual guides. They are an injection molded plastic part that's subjected to thermal cycling and mechanical fatigue. Plastic mechanical properties degrade over time with thermal cycling and become more brittle. They also see cyclic loading from the chain. So what makes you guys think an accumulator will magically solve a fatigue issue!?!? Jesus crist guys....everyone jump off the bridge now!!

You hear chain slap/rattle because the chain spins up to 1300 rpm immediately after start up with no tension on it...then quickly settles back down to idle. Wtf....

Whoa whoa yourself.....Oil pressure does play a roll in this as well. Yes, the plastic guides do degrade with thermal cycling and fatigue and that is why guide failure is more prevalent in older cars but if you can reduce the "shock loading" on the guides there is less chance of them breaking. The rattling that we hear is the chains slapping around because the tensioners have not been pressurized, as the chains are flailing around they are hitting the guides and that is what breaks them (shock loading). So while there is little that we can do to prevent the guides from getting brittle over time we can make their lives easier by not allowing them to get beaten to a pulp by flailing chains.....to do that you need to have the tensioners providing tension on the guides so there is not slack in the timing chain and to do that you need to have oil pressure before the car is started.

Before you go off and tell us that we do not know what we are talking about take a look at the big picture.


Cheers,
Jim