-
Hey Guest!
British Car Forum has been supporting enthusiasts for over 25 years by providing a great place to share our love for British cars. You can support our efforts by upgrading your membership for less than the dues of most car clubs. There are some perks with a member upgrade!**Upgrade Now**
(PS: Upgraded members don't see this banner, nor will you see the Google ads that appear on the site.)
Hey - did you know if you click on the title of a thread it will take you to the first unread post since you last visited that thread?
but were afraid to ask: 
STOP!! Never post your email address in open forums. Bots can "harvest" your email! If you must share your email use a Private Message or use the 
smilie in place of the real @
Pretty Please - add it to our Events forum(s) and add to the calendar! >> 
What Oil to use for first start on rebuild?
- Thread starter Jbird
- Start date
Share this page
I would say, breakin the first 500-750 miles with a conventional 5w-30 and then swap it out for Mobil 1 10w-30 synthetic thereafter.
For the rings to seat well, get on the highway and in 5th gear and slow down to about 30mph and floor it up to about 70mph and let off the throttle and let the car slow back to 30mph then floor it again up to 70. Do this about 10 times. The point of this is to heat the rings up to max temp quickly under acceleration and then it cools them back down under deceleration and the rings will break in just right.
For the rings to seat well, get on the highway and in 5th gear and slow down to about 30mph and floor it up to about 70mph and let off the throttle and let the car slow back to 30mph then floor it again up to 70. Do this about 10 times. The point of this is to heat the rings up to max temp quickly under acceleration and then it cools them back down under deceleration and the rings will break in just right.
Offline
<blockquote><font size="1" face="Verdana, Arial">quote:</font><hr>Originally posted by TR7/8 TPI:
I would say, breakin the first 500-750 miles with a conventional 5w-30 and then swap it out for Mobil 1 10w-30 synthetic thereafter.
<hr></blockquote>
Just for the sake of discussion;
A properly built engine does not require special break in. By properly built I mean that all machining, parts, & assembly are correct.
New cars don't require break in, race cars don't require break in, aircraft don't require break in, boats don't require break in, they just go out & run them.
This being said, an engine which does not have everything correct may take a long time to or never break in.
D
[ 02-21-2004: Message edited by: Dave Russell ]</p>
I would say, breakin the first 500-750 miles with a conventional 5w-30 and then swap it out for Mobil 1 10w-30 synthetic thereafter.
<hr></blockquote>
Just for the sake of discussion;
A properly built engine does not require special break in. By properly built I mean that all machining, parts, & assembly are correct.
New cars don't require break in, race cars don't require break in, aircraft don't require break in, boats don't require break in, they just go out & run them.
This being said, an engine which does not have everything correct may take a long time to or never break in.
D
[ 02-21-2004: Message edited by: Dave Russell ]</p>
Mark Beiser
Jedi Warrior
Offline
<blockquote><font size="1" face="Verdana, Arial">quote:</font><hr>Originally posted by Dave Russell:
New cars don't require break in, race cars don't require break in, aircraft don't require break in, boats don't require break in, they just go out & run them.<hr></blockquote>
New car, racing and aircraft engines are built with MUCH tighter tolerences than the typical engine rebuild.
Unless you get the engine blueprinted, wich costs a lot extra, or takes a ton of extra time if your doing it yourself, you need to be fairly conservative with it in the first fe hundred miles.
Our old tech engines have iron compression rings scraping against an iron cylinder wall. They need time to seat properly, even if the engine is blueprinted to racing tolerences. Race cars, new cars and aircraft use a variety of different alloy rings and smooth finished cylinder walls.
New cars don't require break in, race cars don't require break in, aircraft don't require break in, boats don't require break in, they just go out & run them.<hr></blockquote>
New car, racing and aircraft engines are built with MUCH tighter tolerences than the typical engine rebuild.
Unless you get the engine blueprinted, wich costs a lot extra, or takes a ton of extra time if your doing it yourself, you need to be fairly conservative with it in the first fe hundred miles.
Our old tech engines have iron compression rings scraping against an iron cylinder wall. They need time to seat properly, even if the engine is blueprinted to racing tolerences. Race cars, new cars and aircraft use a variety of different alloy rings and smooth finished cylinder walls.
Offline
MD,
I fully agree on the cam break in, 30 minute fast idle. I just consider this to be part of a first start. Not a driving procedure. It is good that you mentioned it though, it is one of the most critical parts of a rebuild & some folks may not know about it.
Mark,
I got past the back yard stage 40 years ago. Everything perfect is the only way to go. I sometimes forget that not all folks are so inclined or can afford it. There also seem to be differences of opinion in the definition of restored - rebuilt cars.
D
I fully agree on the cam break in, 30 minute fast idle. I just consider this to be part of a first start. Not a driving procedure. It is good that you mentioned it though, it is one of the most critical parts of a rebuild & some folks may not know about it.
Mark,
I got past the back yard stage 40 years ago. Everything perfect is the only way to go. I sometimes forget that not all folks are so inclined or can afford it. There also seem to be differences of opinion in the definition of restored - rebuilt cars.
D
PC
Obi Wan
Offline
I am reminded of a story about Mark Donahue. Donahue and Penske were getting all of their winning motors from Traco in California. They were fast and bulletproof. Even their Ferrari motors were sent to LA for re-work (Traco got more power out of them than the factory did!).
At one point Mark was hearing a lot of complaining from other teams that the Traco motors weren’t reliable. Mark asked Traco what was different about how his motors were handled. He was told that they weren’t. All customers got the same service. He then went to see how the other teams used their motors. They all stuck them in race cars and drove them hard. Mark, on the other hand, always insisted that his team follow a methodical break-in schedule. He kept doing so and winning.
PC.
At one point Mark was hearing a lot of complaining from other teams that the Traco motors weren’t reliable. Mark asked Traco what was different about how his motors were handled. He was told that they weren’t. All customers got the same service. He then went to see how the other teams used their motors. They all stuck them in race cars and drove them hard. Mark, on the other hand, always insisted that his team follow a methodical break-in schedule. He kept doing so and winning.
PC.
I disagree on no break-in, Forget rings they seat in a few minutes or never ( if you used too much lube) the thing that wants some care is the camshaft/lifters. Most builders will want it babied for 30 minutes or so then checked for valve lash before real driving sets in. I like a nice fast idle(2000 2400 rpm) 20 to 30 minutes. drain and refill with the oil of your choice.Re-torque the head when cool and re-check the lifters. Go synthetic if you got $$$ to burn, I have NEVER seen a single test that found a difference in the long term vs good (cleaner due to more changes)regular oil.In fact if you ask a racer they NEVER use synthetic as it will not give good cam life.
MD(mad dog)
MD(mad dog)
britishcarfreak
Jedi Hopeful
Offline
I'm no expert but here's what i had to do on my rebuild (according to the builder who is a racer).
Keep it under 4krpm as much as possible.
Avoid straining it in high gears i.e. always pick a gear that results in unstressed running between 2000 - 4000 RPM whilst on the road.
We also gave it some absolute thrashings in the first few days winding it all the way up to 6750 but only at short bursts.
We ran it for 30 mins at a 2500-3000 on the first start. This is tricky because unless everything is perfect you may not even be reliable enough to get that continued 30min run.
I had running in oil - don't know the grade - but I was told it was very thin and did not offer much protection to the cam etc. at high revs - hence the warning to avoid high revs for long periods until the change to normal oil.
I seem to remember that the 30 min running on first start up was to gaurantee hardening of the cam faces and lifters etc.
I've heard from plenty of people that the process of winding all the way up and then coasting back down over and over on a long stretch of highway is the best way to seat the rings.
I was also warned to avoid any high revs under a no-load situation. i.e do not sit there and wind it out to redline in neutral. Can't remember the reason though.
The guy that built my motor goes straight out on new engines and races them - all he does is the standard 30 min first go. But - he always drives the car to its first event rather than trailer it. I guess that way he gets an hour or so of real road driving before the first use.
I guess though that a motor built for race v's a motor built for street is quite different as the life expectancy of a race motor is a lot less + the cylinder fit can be a bit sloppy on purpose if aiming for a high revving motor.
Just my personal experience - not opinions stated here
Keep it under 4krpm as much as possible.
Avoid straining it in high gears i.e. always pick a gear that results in unstressed running between 2000 - 4000 RPM whilst on the road.
We also gave it some absolute thrashings in the first few days winding it all the way up to 6750 but only at short bursts.
We ran it for 30 mins at a 2500-3000 on the first start. This is tricky because unless everything is perfect you may not even be reliable enough to get that continued 30min run.
I had running in oil - don't know the grade - but I was told it was very thin and did not offer much protection to the cam etc. at high revs - hence the warning to avoid high revs for long periods until the change to normal oil.
I seem to remember that the 30 min running on first start up was to gaurantee hardening of the cam faces and lifters etc.
I've heard from plenty of people that the process of winding all the way up and then coasting back down over and over on a long stretch of highway is the best way to seat the rings.
I was also warned to avoid any high revs under a no-load situation. i.e do not sit there and wind it out to redline in neutral. Can't remember the reason though.
The guy that built my motor goes straight out on new engines and races them - all he does is the standard 30 min first go. But - he always drives the car to its first event rather than trailer it. I guess that way he gets an hour or so of real road driving before the first use.
I guess though that a motor built for race v's a motor built for street is quite different as the life expectancy of a race motor is a lot less + the cylinder fit can be a bit sloppy on purpose if aiming for a high revving motor.
Just my personal experience - not opinions stated here
Rick O.
Jedi Trainee
Offline
I agree that the initial cam run-in is crucial to a happy marriage (or is that civil union?) between lobe and lifter. Regarding run-in lubricants, you may be surprised with my experience owning a new Honda Element. Owner's manual states that the "special" factory engine oil fill is not to be changed until the 5,000 mile mark. Apparently it is fortified for the initial run-in period.
Offline
Hi Guys,
Ok I'm gonna throw my two cents in here. I have only built about ten or so motors by myself so I know most of you have more experiance than me. What I have always done after the 30 minute idle was just to go out for about an hour drive keeping the motor in an easy rpm and allowing things to loosen up a bit if the motor was tight and the rings to seat well. After that I just drive it normally for 500 miles ( not really jumping on it too hard) and change the oil. Also I always change my oil every 2000 miles I find it keeps the inside cleaner and the motors in overall better shape.
Cheers,
Walter
Ok I'm gonna throw my two cents in here. I have only built about ten or so motors by myself so I know most of you have more experiance than me. What I have always done after the 30 minute idle was just to go out for about an hour drive keeping the motor in an easy rpm and allowing things to loosen up a bit if the motor was tight and the rings to seat well. After that I just drive it normally for 500 miles ( not really jumping on it too hard) and change the oil. Also I always change my oil every 2000 miles I find it keeps the inside cleaner and the motors in overall better shape.
Cheers,
Walter