The Lotus Cars Community banner
1 - 17 of 17 Posts

·
Registered
Joined
·
156 Posts
Discussion Starter · #1 ·
So my 94 S4 engine has been rebuilt and I am going to put her back in this weekend (lost timing belt while running) and have a question about the break-in period and what oil should be used. So, how long should the break-in period be and what oil should be used? What operating parameters should I follow during the break-in period?

Thanks!
 

·
Registered
Joined
·
861 Posts
use a "break in oil." they usually have a high zinc or zddp content. You won't find these at the corner auto parts strore, though.

amsoil, redline, joe gibbs, comp cams, royal purple....they all make special break in oils.

Did you lube up the cam lobes too during assembly? Not sure about these cars, but it is good general rule to use a thick moly assembly lube on all the cam lobes. These engines have a cam-over-bucket design which is very similar (frictionally) to a flat tappet cam/lifter setup on an american V8.....and using moly lube is the way to go for break in on these types of cams.
 

·
'94 S4
Joined
·
238 Posts
Start w/the owner manual's recommendations about rpm & mileage then stand back for the barrage of opinions & advice about oil and break-in protocol. In the meantime, I'd like to hear more about that lost timing belt - age, tensioner, whatever it was that happened.
 

·
Registered
Joined
·
1,235 Posts
I use a moly assembly lube when rebuilding, then a high quality dino oil for 300 miles, and then on to the synthetic of your choice. There are a million opinions on what long-term oil is best. I have used Redline 20/50 with good results. I recently switched to Mobil V-Twin 20/50 after considering a lot of what has been written on this forum.
 

·
Super Moderator
Joined
·
4,265 Posts
I read your entire TLF thread on the belt - I'll boil down that the timing belt is suspected of failing due to:

1. belt was older than originally thought
2. oil pump cam was chamfered in an odd way that may have contributed to failure.

Great detail on that thread.
 

·
Registered
Joined
·
3,570 Posts
For a break-in oil I use what would normally be used in the motor and add a quart of Marvel Mystery Oil. If you replaced the camshaft and/or tappets you need to follow the break-in recommendations from the cam manufacturer. Typically they want you to get to 2,000 RPM's for 20 minutes just as soon as you can get good oil pressure up. Once you get that done and start driving you should not hold the RPM's at a fixed speed for the first 500 miles or go over 60 MPH. Drive easy till the motor reaches operating temperature. After the first 500 miles replace the oil and filter and the break-in period is over. For the break-in oil it is suggested you go with a high ZDDP oil or use an additive to coat the surfaces. Current wisdom is that if you break in with high ZDDP oil you don't need to add more than what is in today's modern oils after break in. This assumes you used the correct assembly lube on the cam lobes during assembly. Most of the break-in wear occurs just as soon as the motor starts and before you get oil pressure up. That's why on many motors the builder will prelube or pressurize the oil system before trying to start the motor. The 2 most critical wear areas are the cam lobes and the piston ring/cylinder walls.
David Teitelbaum
 

·
'94 S4
Joined
·
238 Posts

·
Registered
Joined
·
1,289 Posts
Did you replace the pistons and/or rings? If not, I would fill it with xxW-50, drive it gently for 50-100 miles, and then change the oil and filter.
 

·
Registered
Joined
·
156 Posts
Discussion Starter · #10 ·
Yes, rings were replaced. Does that mean I should use dino oil for the first couple hundred miles? Is there any special considerations needed due to the nikosil?

Thanks
 

·
Registered
Joined
·
1,976 Posts
One of the biggest no no's is not varying the throttle/RPM's during break in..
 

·
Registered
Joined
·
4,948 Posts
The Esprit 4 cyl uses a Nikasil coating on the cylinders (as you probably already know), the Nikasil (nickel plating with inclusions of silicon-carbide crystals). The silicon-carbide is very hard, close to diamond, and oleophilic (holds onto the oil). I use the oil that I would normally use (synthetic), that dino oil can leave carbon and crap in there for ever if you use it for break in.

As long as you coated the rings and piston with a little oil before assembly, and you prime the engine with oil before starting, and used Moly based assembly lube... Then the engine will most likely be fine.

Once you prime it with spark plugs and fuel pump fuse removed, then check for leaks or weird things that you forgot...

Then put the plugs and fuel pump fuse back in, and let the fuel pump run a few times, turning the key on and off to build fuel pressure.

Then start the engine and quickly look for leaks! Listen for weird sounds, and look at the timing belt to see if it is flapping or running towards one end of the cam.

Turn it back off and look for leaks every where. Look for signs of the belts rubbing.

Look for fuel leaks.

Turn it back on and let it idle until the engine is warm to ~82C, make sure the thermostat is opening. Check coolant levels often! Refill as needed burping the front radiator bleed (use gloves). As the coolant gets warm look for bubbles in the coolant! The coolant may swell up, and you may need to refit the header tank cap.

I usually run freescan during the warm up period from cold to 82C, and log the data.

Look at the IAC counts for intake manifold air leaks in freescan. It should be between 20-40 once the engine is warm ,~80C, don't touch the throttle or rev the engine.

Then I usually put the car back on the ground, let it cool off, burp the air out the the radiator, fill the coolant up some more, and then take it for a test drive with freescan recording a log file.

You most likely will get smoke from around the exhaust manifold and turbo. Do not freak out, but make sure it isn't from a leak. There is usually residue on the cast iron that bakes off the first time it gets hot.
 

·
Registered
Joined
·
156 Posts
Discussion Starter · #14 ·
Thanks a lot Travis, great info! Yep, everything was lubed very well during assembly and I will prime with the plugs out, fuel off and have Freescan logging.

One question comes to mind, where should I set my air bleed valve to begin with? I adjusted it before and got it perfect. Should I just leave it as is and adjust later if needed?

Thanks again, John
 

·
Registered
Joined
·
861 Posts
one thing that is really important on an intial startup after a new build is to prime the oiling system!!!!

if you can't (or don't want to) gain access to the oil pump pulley to spin in up, you could also get one of these (or make your own.) GOODSON : Engine Assembly Tools : Engine Pre-Lube Tank : EPL-120

never tried it on an Esprit, but it would seem easiest to release the timing belt tensioner, slide the belt ff, and then get a 90* air racthet onto the oil pump pulley and spin it up until you get full oil pressure on the cockput gauge.
 

·
Registered
Joined
·
156 Posts
Discussion Starter · #17 ·
Got it, Thanks Travis.

Yeah I remember the "good ole days" when you could prime the oil system via the distributor gear and a drill :)

There is no way I am messing with the timing belt or even the tensioner. The plan is to pull the plugs and fuel pump fuse and turn it over until I see a bit of pressure.
 
1 - 17 of 17 Posts
Top