F355 oil pump chain conundrum

Hello all,

my first post here on FC so hello to everyone!

I am building an F355-engined S1 Lotus Exige track car (will start another thread on that for anyone that's interested!) and am nearly ready to connect my F355 engine and gearbox for the (hopefully) final time.

The engine is a race converted motor, that was previously in a single-seater racecar running a PACE 6-stage dry sump pump externally via a belt drive.

The engine has already been fully rebuilt, timed and is fresh to run.

For my application I am returning to standard sump and oil pump, and this is where my problem lies. I have the standard oil pump, brand new oil pump drive chain, and all the tensioner parts ready to fit. However I will only be able to get access through the sump pan to fit the parts, as I strongly do not want to have to remove the engine front cover at this stage.

Is this possible? I believe that all the parts were removed this way, but the old chain was removed by splitting a link to get it off the crankshaft.

I suspect that I will have to use a part such as this in order to complete the task?

Chain Link oil pump drive FEBI for CHRYSLER 300 C Touring (LX) PT | eBay

if anyone has ever attempted similar, or knows if there are any other parts it is impossible to fit without removing the front cover please let me know?

kind regards,
Patrick

 

pulled the sump pan off this afternoon, and as long as I can find away to break and re-fasten the oil pump drive chain acceptably then there is enough room and access to do what I want which is to fit the entire standard oil pump system, including tensioner and guide pads.

here is a pic, I'll let you know how I get on.

cheers,
Patrick
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Please do start another thread on the build. Do you have any pics of the car it was installed in before?

 

The oil pump chain has no master link. Ferrari learned the folly of that design in 1986 in the form of quite a few badly damaged Testarossa motors. The incidence of failure would be considerably higher in a quick revving 355 motor. Also the tensioner assembly cannot be installed with the front cover in place. The front cover needs to be removed.

 

The front cover is gonna have to come off. There isn't another way to get the chain over the front of the crank and the sprocket. If the 355 oil pump chain tensioner is the same as the 348, there is also a little bit of a "trick" to getting the chain tentioner ready for install, which is best done with the front cover off. Here is how I did it on my 348. http://www.ferrarichat.com/forum/technical-q-sponsored-algar-ferrari/438576-348-engine-out-major-17.html

 

Well thanks for the thoughts, but I managed to do it with the front cover on, just accessing through the sump pan area. I used a brand new split link similar to this:
06B-1-NO26 Chain Connecting Link 3/8" Pitch BS Simplex Connecting Link | www.rollerchains.co.uk
I'm not worried about a failure. Mercedes use these style of links on their oil pump systems, and I have even seen them employed on an OEM cam drive system.

I carefully ground through the rivets on one link of a brand new F355 chain (attached pic). Then you can carefully thread the chain around the crank by turning over the engine. Re-fit the split link, and you have just about enough clearance to the nearest crank main bearing cap to refit the guide pad and the tensioner assembly (spring retracted). Fit the oil pump assembly next, with the sprocket already fitted to the pump.

Finally release the tensioner spring into place to tension the chain. Job done! Not easy and small fingers are a must! It probably helps that I design engines for Triumph Motorcycles here in the UK so am used to this sort of thing.

I will do! In the meantime I have a blog here: S1 lotus elige

No pictures of the previous car I'm afraid, but it was a single seater (most likely a Dallara chassis of some sort) destined to run in the EuroBoss series here in Europe.

I will be running the engine on a Pectel SQ6 engine management system when complete, with electric waterpump. Couple more pics attached for interest.

kind regards,
Patrick
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I am building a project 348 motor and some of the things I am doing would probably be questioned by some of the more experienced builders here.
But even I don't think I could bring myself to do that to the oil pump chain.

I am truly hoping that doesn't come apart at some point. Fingers crossed.

 

+355

Not too many Mercedes can match revs with a 355 engine. I would remove the front cover and use an unaltered chain. It is a lot of extra work, but if the chain fails things will get very expensive quickly.

 

I am surprised how little technical knowledge and paranoia there is on this forum! I suspect partly because Ferrari owners are not of a persuasion to perform their own maintenance in general?

To address some of your concerns:

Many oil pumps run at faster than engine speed via use of an idler gear for efficiency. So actually a great many pumps will have sprockets exceeding the 9000rpm crank speed of the F355.

I've found a number of Mercedes that specify the use of a split link for service of their TIMING CHAIN. (the torque-to-turn and chain loads through a timing drive system are orders of magnitude greater than what is required to turn an oil pump).

I am curious - what exactly do you people expect the mode of failure to be? Fracture of the split link? Or the cotter plate somehow fracturing or falling off enabling the split link to fall out?

The tensile strength of the split link is equal or greater than that of any of the individual standard links. There is no axial force applied that could cause the cotter plate to wear. The only risk that I think is viable could be from increased wear due to chain resonance due to the minimal change in mass (1-2grams added).

Bear in mind that the original supplier of the OEM chain will have been able to produce it for a manufacture cost of around $2.

 

I agree, a master link should not really be an issue. However, bear in mind that it is not so much the forces on the chain that can lead to a master link falling apart, it is the accelerations that the chain will endure during its operation. That includes acceleration from combustion pulses as well as the turning circle of the chain versus the rpm and last, the load that the tensioners may put on the link.
Make sure that the spring on the link is facing the correct way, is all I can say. Or alternatively, fuse the master link in place by small TIG welds or similar. That should silence the critics...

 

This has bad idea written all over it!!!

 

I think the failure mode is the spring clip falling off, not the strength of the split link itself.

 

Bingo!!!!

 

What ever experience and technical knowledge you have....I have more.

 

Yea but he's a "Powertrain design engineer" donchaknow.

I've seen master links come off on a few occasions. He's upping his risk factor by using one here. Chances are good he'll be lucky and when the engine blows it will be because of something else.

pat_t, excuse us if we put you on a rather short leash here. You're not the first "engineer" that appeared out of nowhere and claimed to be smarter than the average bear. Some of us actually have real-world knowledge and experience and possibly a degree or two to back it up.
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Hi Pat,
Good luck with your split link oil chain. Let the board know how it works out.
Please understand that some of the people on this board have more experience with Ferraris than you can imagine.
We aren't all haters on here, people are trying to answer your question and give you a knowledgeable answer.
Cheers,
XENU

 

None are haters but when he comes here with a "you guy don't know anything" attitude he deserves what he gets. Blow off suggestions? No problem. Be an ass about it? Different story.

 

Rifledriver, forgive him, for he doesn't know who is on FChat.

 

I excuse you. I already have my IMechE acredited BEng in Engineering thanks.

Here's my LinkedIn, add me if you like. https://www.linkedin.com/profile/view?id=124415963

Just for your interest I spent my day yesterday here at work on Ricardo's VALDYN software designing cam profiles for a new engine platform we have in development. VALDYN - 1D Kinematics and Multi-Body Dynamics

Today I was offering my (still growing) knowledge of gravity die casting knowledge to a colleague who is working on some changes to a cylinder head we have in production. Tomorrow I might be involved in engine simulation, next week in performance development on one of our eight engine dynos, the week after maybe do an emissions or fuel economy study in MatLab. Luckily where I work there is never a dull moment.

I've seen my fair share of blown engines both on the dyno and on track, (unfortunately more than I would like in the past 12 months! ) if my F355 engine goes pop like you say it most likely will be because of something I have done, after all I am running it far from it's original design criteria, in a car that was never designed for it.

Luckily for the Internet though there are people like me who enjoy pushing the boudaries and seeing what can be done. This allows people like you to criticise. If it goes tits up I'll still have enjoyed the experience of tinkering in my garage for a couple of years. If it doesn't I should be left with a track car with about 400bhp and a 750kg wet kerbweight and some reasonable aero! Which certainly will be a thing to enjoy

Best regards to all - I'm not trying to annoy anyone, just dislike being told I can't do something by those who probably have no idea...

 

Not that I particularly care, but if that isn't the pot calling out the kettle I don't know what is

 

Hi Pat

Good luck with your project.
I've blown up more motors I can remember in the last 50 years playing around and will continue grenadeing another in the near future.
If I wanted to be safe I would wear suspenders and a belt.

 

Interesting solution. I do admire your ingenuity.

For me the big hang up with the way you did it is because you already had engine out of the car, and the sump pan off, that is half the battle. Had the engine been in the car, and you were in a pinch, then I think I would have been more accepting of your method. Myself, I would have just taken the front cover off. A quick blip on the crank bolt with and impact wrench, and off comes the pulley. Then a handful of nuts, and off comes the front cover. Sure it would have had to have been resealed, but that isn't a big deal.

Having said that, thanks for sharing your solution. I think it will be valuable for someone else if they do get stuck and need a solution to fix the oil chain with the engine in the car. Hope it holds up for you. Give us periodic updates on how it's running.