Engine break in

[CaptRon66]

I will be hopefully starting up my engine in the next few weeks. Mercruiser 165 straight 6 and breaking in the cam. Can anyone tell me if there is a break in oil or additive that needs to be used? Should I use the straight 30w or the newer merc multi weight? The engine has sat for 10 years after rebuild and never started.

 

[Don S]

Re: Engine break in

Straight 30W oil will work fine. Break it in per the OEM manual and you will be fine.
Change the oil and filter at 20 hours.
PS: you can find the OEM service manual downloads in the Adults Only sticky at the top of this forum.

 

[rodbolt]

Re: Engine break in

sitting 10 years and never started?
remove the distributer, reprime the oil system.
any breakin lube,usually lubriplate, will be peanut butter and most liky you will suffer a lobe failure at startup.
seen it more than once.

 

[Don S]

Re: Engine break in

He's doing that rodbolt. http://forums.iboats.com/showthread.php?t=370266

 

[jtybt]

Re: Engine break in

Really important to use a break-in oil or additive for new flat tappet hydraulic cams.

Learn the reasons...

http://www.valvoline.com/faqs/motor-oil/racing-oil/


There are more than one ZDDP additive manufacturers so this is not an 'ad' for valvoline.

 

[CaptRon66]

Re: Engine break in

Don, .I couldn't find the break in procedure in the merc service manual for my engine. Still looking.I read a link of yours on a different thread .It didn't mention cam break in. Would you not break in the cam around 2000 rpm varying the speed? Here is what I found searching old threads:
20-Hour Break-In Period
IMPORTANT: The first 20 hours of operation is the engine break-in period. Correct
break-in is essential to obtain minimum oil consumption and maximum engine
performance. During this break-in period, the following rules must be observed:
? Do NOToperate below 1500 rpm for extended periods of time for the first 10 hours.
Shift into gear as soon as possible after starting and advance the throttle above 1500
rpm if conditions permit safe operation.
? Do NOT operate at one speed consistently for extended periods.
? Do not exceed 3/4 throttle during the first 10 hours. During the next 10 hours,
occasional operation at full throttle is permissible (5 minutes at a time maximum).
? Avoid full throttle acceleration from IDLE speed.
? Do NOT operate at full throttle until the engine reaches normal operating
temperature.
? Frequently check engine oil level. Add oil as needed. It is normal for oil consumption
to be high during the break-in period.

Rodbolt, do you think I'll be ok just pre-lubing? Or should the cam be removed and lubed?

Charlie,thanks.I'll try to find an oil with zddp. Are the additives compatible with most 30W oils?
__________

 

[Don S]

Re: Engine break in

There is no "Cam Break in" period. Any Merc or Volvo breaking says nothing about a specific "CAM" breakin procedure. Follow the list you just posted and your engine will give you years of service. If it was put together right. Are you sure it even had new cam and lifters installed?
If you are worried about the cam lobes, pull the lifters out and dump some 30W oil in the cam lobes and put the lifters back in.

 

[JustJason]

Re: Engine break in

Break in is a funny thing. It's more about breaking the customer into the handleing characteristics of the boat more than it is worrying about the engine.

If the engine was re-built/remanufactured correctly, with everything being measured twice by a compentent mechanic/machinist, then there is nothing to worry about. Start her up, let her warm up, and take it out and rip it up.

Before you attempt to start the engine, change the engines oil and filter, and use a priming tool or an old modified distributor and run the oil pump with a drill. 1 full minute would do it, but if the engine sat for 10 years i'd probably run the drill for 5 or so minutes. At the same time I would hook up an oil pressure gauge to make sure that your getting at least a few psi off the drill.

If the engine has a points ignition system your probably going to have to clean the points up at minimum, or replace them, to make sure the ignition system is working correctly.

Good luck, let us know how you make out.

 

["G"]

Re: Engine break in

It's hard to find a 20 wt. non-detergent oil these days but that's what the old timers will tell you is best for break in oil. Multi grade oils aren't good because of high detergent but they are better than a heavy motor oil. The object is to get SOME friction on the rings so they seal to the freshly honed bore. That's the idea of a "break in" period, seating the rings, especially those hard chrome ones...

The API (American Petroleum Institute) web site says; use a light weight motor oil like 5-20 because it gets around faster at start up. Since wear begins at start up, if the oil is heavy it will take a longer amount of time to get around thus greater engine/bearing wear.

If you used the cam grease they provide for new cam installation, that will be there until it gets washed away. We always used Merc's multipurpose grease for assembly and never had a failure from that.

Can't hurt to pre-lube your cylinders. A hand or electric pump connected up to your block (where the sending unit goes) will work as well as pouring/squirting oil in the cylinders.

Never built an engine that failed because of lubrication at start up. I still do 'em the same today albeit... far fewer as I'm not in the trade anymore.

 

[CharlieB]

Re: Engine break in

A motor left setting for 10 years before firing would cause me to wonder about cyl wall surface rust and rings sticking to the wall.

Before attempting to turn and fire this motor I would add an ounce of oil to each cyl and after pre-lubing as earlier posted, then gently bar the motor over without the plugs by hand a few turns to spread the cyl oil.