timing chain adjuster

Friday morning I got an email which I did not read until later saying that the tech hoped to have the front cover off motor Friday PM. When I called Friday PM they said it appears impossible to remove cover with motor in car. They were going to try to lift motor a bit to get it to clear. Apparently the oil pan needs to come too off to get the front cover off; not sure that was correct explanation. I will know tomorrow if engine is coming out or not.

If it comes out I do not plan to willy-nilly change parts just because the motor is out. I will change that nasty little coolant hose for sure. I will look to this forum for what would be the ESSENTIAL parts to change if motor is out. What are the weak links in the water / oil pump? Is it just the seal between the two? How tough to change? I look for your collective advice.
Ken

 

You need to remove the engine to change the timing chain adjuster foot. The other guide is worn also and would need to be changed.
These engines were designed to be removed and serviced and at 65K your valve guides are way past due. You need more than a chain and tensioner foot.

 

Fritz and All
The motor will be out by end of day today. Shop will do several jobs that require the motor out including: water pump rebuild, front and rear main seals and motor mounts. I do not disagree that a valve job would bring the motor back to life, but that is something that can be done with the motor in the car. So from a cash flow standpoint that will wait for another day, likely next winter.

The bill is still a 4-digit number and I intend to keep it below 5-digits. Although the chain guide on right side of motor is considered NLA, my shop has found one ($500). I hope to take pictures of motor and engine bay once engine is set on stand and car has a big gaping hole in it!
Ken

 

I agree that NLA chain guides are a concern, especially as ken's car has similar mileage to mine. I wonder if it's possible to apply a DLC finish to the wear area. Ken, any chance you can get a few pics of the worn parts and compare those to new?

 

GT
I hope to see the car tomorrow PM and will have my camera. Engine should be out but not sure front plate will be off yet. In any case I should be able to take a pic of the new part and some time later the old one. I will also ask where they found the NLA part. I know my shop makes a lot of NLA items when needed; but I am not sure what the wear material is yet.

More to follow but maybe no re-post until late in the week as I am out of town after I see the car.
Ken

 

Ken, The original tensioner was cast aluminum and the new after market one I brought from England was machined out of a billet and then had the rubber wear surface vulcanized on it.
The pivot hole must of been distorted in that process because I had to ream the hole and file the width for fit. At $250 for the aftermarket part and $600 for the OEM I felt after the hand fitting might no be worth it.
http://www.ferrarichat.com/forum/365-gt4-2-2-400-412/238081-chain-guide-wear-advice.html

 

I am surprised that the remake used the process of vulcanizing to attach the wear surface material. I am also surprised that rubber, or a composite of, was used as the wear surface. There are several formulations of nylatron, and it's derivatives, that have superior wear characteristics, heat and chemical resistance, pressure tolerance, and machine ability.
NLA parts should be re-engineered to provide better than OEM performance because it appear that improving the assembly process, including removing the engine to replace these parts, isn't easily done. With better wear parts the need for this expensive repair would not happen before the end of the life of the chain.
Ferrari's timing belt use in newer cars, for what ever reason, is an example of putting longevity in the back of the bus, just like the antiquated wear surfaces for the chain followers in the 365/400/412 engines.

 

No kidding!

 

Ferrari have gone back to using timing chains on all their new cars, given up on the idea of rubber bands..

When you consider the service life of a chain vs the belt, the chain wins every time. Chains only have to be replaced based on use ( belts will deteriorate from sitting) and you never hear of engine failures from broken chains. The average 308 will have probably had 7 belt services by the time (35 years, belt every 5 years) a 4xx series needs a timing chain, and perhaps guides.....

M

 

Here are some pics showing the front cover and it tells the story why the motor has to come out to change the tensioner. The first picture shows the culprit; this is the tensioner pivot that clearly could have been engineered to be removable out the front cover and the tensioner could have been changed in one hour.

I posted some additional pictures on the thread about the tensioner and guide material. (Also, some pics about the pan coating peeling on that thread.)
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This could be a project for Verel (?) the guy who makes NLA parts.

A possibility would be to send the old part in and "they" would apply some new "space age" material that would be better than rubber.

 

Thanks for those pix Ken!!
Back in the day, Ferrari engineered their cars to hold you hostage to the service departments

 

Kind of surprised Verell hasn't.

 

Ken
good stuff you are in there to get things sorted, apologies couldnt remember how the tensioner came in or out alas the pivot. please check on the other thread for my thoughts re guide wear, good to do front cover work it will all be fine keep up the good work
Regards
Alastair

 

Although the cost of the 'little project' has more than doubled, the good news should be that there are no more engine leaks!! If I consume oil now it will just tell me its time for an even more expensive job!@! There was a pretty serious leak on the back of the left cam bank and since they are doing the valve covers and valve adjustment this leak will be history. Front main seal, rear main seal are all being done.
Ken

 

This is the first I've heard of the need.

QUOTE=Ak Jim;143034546]This could be a project for Verel (?) the guy who makes NLA parts.

A possibility would be to send the old part in and "they" would apply some new "space age" material that would be better than rubber.[/QUOTE]

That does sound like an interesting project. I'll put it on the list of products to look into.

Altho, I seriously doubt it's classic rubber if it's running in a hot engine oil bath.

 

I will email my shop this evening to save both guide and tensioner for anyone that wants to build a better mousetrap.
Ken

 

I heard from a fellow 400i owner that to change the front brake lines, you have to remove the motor!! He did so when motor was out, but I did not. If I ever need to change them and this is true I will cut them out with a saw and reroute the lines to be accessible!!
Ken

 

This thread really shows a big vulnerability in these engines.

 

Now they are designed for you to be held hostage by the bankers.

 

If I could get them it would greatly speed up development of a rebuild process or a replacement part.

 

Dave, you bring up a good point. I'm wondering if the problem is how the adjustment is made by using the sound of the chain. I'm wondering if some of the wear problems are related to over tension on the chain. I think the measurement with the 20kilos and 1mm deflection is a better way to go.

The real answer would be for someone to adjust it by the sound method and then take it apart and measure by the deflection method. The difficult part is I don't think you can simply take the cover off of the cam sprockets because of the o ring seals. Can someone confirm this?

 

Jim, The problem is using one chain to drive four cams. The factory recommends changing the chain every 50,000KM. That is a short life span even tensioned by the factory.

 

Looks like a bunch of us are going to need an engine out service!

 

Yup.
Dave that is true. I tried to ignore it and I wore a grove in my chain housing. Live and learn.
The valve guides also have an extremely short life span.