Important Notes on Engine Assembly and Break-in
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- เผยแพร่เมื่อ 12 ก.ย. 2024
- Engine break-in and assembly tips and tricks with Lake Speed Jr. from Total Seal Piston Rings (and previously with Driven Racing Oils) and LN Engineering’s Charles Navarro. Even with the best quality parts, if you don’t have everything right you can still have less than perfect results. Learn from our combined experience on what you can do to have the best possible results from your engine rebuild with a focus on engines with Nikasil plated cylinder bores like those used in Porsche engines. Even before you break-in your engine, there are many important steps including cleaning, assembly and lubrication, and tuning that can directly affect breaking in a new engine.
I have 7K miles on my LN 3.8->4.0 build I did in my garage on 2005 Carrera S finished March 2020. Followed LN instructions provided with pistons and nickie sleeved block from LN. I brushed BR oil using machinist brush on all cylinder walls and piston rings+skirts (after copious amounts of cleaning with kem wipes etc.!) during assembly. After start up issues were resolved (different story)...warmed up ...then hard acceleration and deceleration after warm up for 20-30 min. At the time follow on instructions seemed to be a bit different and suggested 200-400 miles on break in oil. I avoided highway drives (steady RPM) and stuck with mountain roads for full time 400 miles. Switched to HR 10w40 oil for next 3K miles...then to DT40. I am a happy man!
Cleaning all the parts before and again during assembly is one of the most important (and often overlooked) steps followed by proper break-in. Great job!
Excellent info guys, thank you !
My fresh VQ build couldn't get pressure from cranking (wasn't packed with vaseline, just assembly lube), and just fired it up for 2 seconds, instant pressure.
Sounds like you experienced the same thing we do. The Porsche M96 engine is notorious for not building pressure. Even with the pump packed with Vaseline, they just won't build any pressure on the starter, even with plugs out.
This is why if I can, make a preoiler..if the oil pump is distributor driven.. use an old distributor shaft stripped down
When I was a mechanic back thirty years ago, when I got the block and heads back from the machine shop. I would mount them one at a time on an engine stand and then steam clean them with a no-rust soap in the water supply -- really work over every passage and bore. Then blow dry the whole thing thoroughly. It worked really well. What do you think of this idea?
Not a technique we've ever used. We use a combo of solvent parts washers for heavily soiled parts, jet wash for engine blocks and cases, and ultrasonic washers for final wash. For pre-assembly all we recommend is denatured alcohol and kimwipes for areas like the cylinder bores. Nothing is more effective in cleaning out the honing debris from the crosshatch.
Sounds like I may have messed something up. I built a 2563 engine for my 914. It now has 500 miles on it . It runs strong but I pulled all 4 plugs and did a compression check . Cylinders 1&3 have great compression but 2&4 only develop about 110psi. From what you guys say here it sounds like the fix might be pulling those cylinders/pistons for rehone and rering. Do you guys agree?
It is certainly possible something happened either during assembly or break-in to cause this issue. The most common causes are improper cleaning or over-fueling to cause an issue like this. However as you purchased an engine kit from us, I'd recommend opening a support ticket so we can properly help you diagnose the issue and also what your next step might be.
Great videos. For a factory new 911, can you be more specific about break in. Once up to temperature cycle idle to 6000(?) rpm regularly for xx miles? Then take oil sample for baseline high wear ?
For a factory new 911 (or any other vehicle), there really isn't anything special you need to do. I would follow the same rules of thumb we recommend on any rebuilt engine. Avoid long drives, have lots of thermal cycles in the first 1000 miles, and avoid using cruise control or driving at one speed and rpm. It is very important to vary engine speeds and loads. I'd say after the first 1000 miles it would be a good idea to drain the oil and have it tested. That will give you a good baseline for what the highest the wear levels should ever be in your engine.