Jump to content

Recommended Posts

Posted
8 hours ago, Beaky said:

In regards to running in rebuild engines, I have heard mileage ranges from 500 to 1500, most saying slowly build up the Rev ranges as mileage increases but never red line it.

What are people’s experiences and/or what their engine builders have recommended?

500 miles on mineral oil and no more than 3k rpm, oil change then another 500 miles no more than 4K rpm. Both these with varying rpm, no lugging, no motorways, no constant rpm. The job is to bed in the piston rings, so accelerate and decelerate, find lots of hills etc. Then tappets and engine check/head studs etc and oil change to whatever super duper oil and go drive it like you stole it.

Posted

James - I agree with David. Take a step back and analyse this a bit.

Is the engine noisy when idling or when increasing the revs when not driving - if not then you're looking elsewhere not at the engine. If it's 3rd, 4th and 5th only it could be road speed related rather than engine speed - try to assess this.

As David says for a video at idle and with gently increasing revs - someone may identify something or tell you all is normal

FWIW my wife told me yesterday that the Porsche was definitely noisier than the Merc!

Posted

James, perished mounts won’t amplify the noise but if you put firmer bushes than standard eg polyurethane rather than rubber more NVH gets transmitted into the cabin. Just thought maybe as part of you engine out for rebuild you may have upgraded and now there is more noise. I guess not. 

Maybe it is not gearbox and it is the timing chains with a fubar tensioner or guide. As suggest try and post a video with the noise. 

No doubt Ivan (Proporsche) will be along soon to save the day and explain all. 

Posted
9 hours ago, jamesmckenzie said:

Hi all,

So got the car back today and it's horrendous! I don't remember this noise as bad as this before I have it to them. Sounds like someones pulling a train of large ball bearings over the top of the engine, kind of what I'd imagine chain backlash would sound like.

And the sound is large (not just in 4th and 5th but) in 3rd gear under anything but light acceleration.

Wingnonut, you mentioned particular gearbox mounts in the bar. What does this mean? Could these have perished amplifying a noise?

Car has done 70k miles.

Warmest,

James.

I thought the car was with your specialist James? What did your mechanic say about the noise?

Posted
2 hours ago, Dr Rock said:

500 miles on mineral oil and no more than 3k rpm, oil change then another 500 miles no more than 4K rpm. Both these with varying rpm, no lugging, no motorways, no constant rpm. The job is to bed in the piston rings, so accelerate and decelerate, find lots of hills etc. Then tappets and engine check/head studs etc and oil change to whatever super duper oil and go drive it like you stole it.

Cheers

Posted

All,

The mechanic mentioned the G50 rattle but also mentioned that I should keep and eye on it in case it gets any worse/louder.

I'll record some audio when the rain stops.

Thanks for your help so far.

Best,

James

Posted
On 5/30/2018 at 7:37 AM, Dr Rock said:

500 miles on mineral oil and no more than 3k rpm, oil change then another 500 miles no more than 4K rpm. Both these with varying rpm, no lugging, no motorways, no constant rpm. The job is to bed in the piston rings, so accelerate and decelerate, find lots of hills etc. Then tappets and engine check/head studs etc and oil change to whatever super duper oil and go drive it like you stole it.

I have no scientific evidence to support my findings but the engines delivering the best output (car, motorcycle & boat) have had 20 minutes of running to ensure all is well then a good spanking.   

Posted
13 minutes ago, Leicestershire said:

I have no scientific evidence to support my findings but the engines delivering the best output (car, motorcycle & boat) have had 20 minutes of running to ensure all is well then a good spanking.   

🤣

Posted
46 minutes ago, Leicestershire said:

I have no scientific evidence to support my findings but the engines delivering the best output (car, motorcycle & boat) have had 20 minutes of running to ensure all is well then a good spanking.   

The 20 minutes as I understand it is on first start up to run the camshafts in. 20 mins at 2000 rpm, not idle. :twocents:

Posted
11 minutes ago, Dr Rock said:

The 20 minutes as I understand it is on first start up to run the camshafts in. 20 mins at 2000 rpm, not idle. :twocents:

I thought @Leicestershire was joking! 

Posted
6 hours ago, Leicestershire said:

I have no scientific evidence to support my findings but the engines delivering the best output (car, motorcycle & boat) have had 20 minutes of running to ensure all is well then a good spanking.   

Strangely enough, this is exactly what I heard from two separate Indies................................:o

Posted
On 5/31/2018 at 5:40 PM, Leicestershire said:

Noted. 

Strangely, the article kind of confirms everything anyone is saying in here (on road cars not plane engines).

First 50 hours are a break in period. Fine. 50 hours at say an average of 30mph gives you 1500 miles or so. Check.

Running at say 70% of maximum. Fine. 70% of 6500rpm is around 4500rpm. Check.

So that tallies with the general consensus on running in. 

Is there another section regarding giving her the beans after 20 hours?

Ive always been told to vary the revs as much as possible during the break in of a new engine and to avoid taking the revs too high. Not pootle about in 4th everywhere at 2 or 3000rpm but vary it as much as possible. It’s a gradual build up to spanking. 

Posted

Accumulated wisdom is as Busybee states, no high gear labouring, no high revs and do frequent throttle variations.......to be maintained for as long as one can endure it!.....then throw caution to the wind and bl@@dy drive it!

David.

Posted
23 minutes ago, Busybee said:

Noted. 

Strangely, the article kind of confirms everything anyone is saying in here (on road cars not plane engines).

First 50 hours are a break in period. Fine. 50 hours at say an average of 30mph gives you 1500 miles or so. Check.

Running at say 70% of maximum. Fine. 70% of 6500rpm is around 4500rpm. Check.

So that tallies with the general consensus on running in. 

Is there another section regarding giving her the beans after 20 hours?

Ive always been told to vary the revs as much as possible during the break in of a new engine and to avoid taking the revs too high. Not pootle about in 4th everywhere at 2 or 3000rpm but vary it as much as possible. It’s a gradual build up to spanking. 

Don’t forget the full power take offs.

Most posts within this thread seem to suggest that mincing about for the first 1000 miles is the way to go. The thought of reaching 4500 rpm after half an hour running would scare many 6500 rpm would be considered many months later.

Certainly not suggesting that everyone changes the way they run in engines, rather share an alternative view.

My current 2 wheel toy is a handmade air cooled Italian gem. Before it left the factory it was tested on a rolling road at max engine speed. 

My daily drive is leased and has received daily beatings since rolling off the car transporter Feb ‘16. It currently has 90k miles, patchy service record and it’s difficult to imagine how a vehicle could be punished any more. Yet it always starts without rattling, uses no fluids and returns 50 mpg. It also wears a Vauxhall badge so would assume the quality of engineering is a long way from the over engineered air cooled Porsche flat 6.

 

 

 

Guest
This topic is now closed to further replies.
×
×
  • Create New...