Just bolted & torqued down the crank girdle. Crank seems alittle snug initially, but will spin by hand with some muscle. Is this normal?
Crank was ground .25, using Nissan .25 main bearings that were coated with Tech Line dry film lubricant, lubed with Lucas assembly lube. Measured & ok'd by machine shop. Thanks!
Question for VH the rebuilders...
Re: Question for VH the rebuilders...
First pull girdle off and clean any sort of lube or grease that has been applied and just use some good engine oil to coat all bearing surfaces.
Check for any unusal marks on your bigends from high spots like scratches etc.
put it all back together and check your end float- should be betwwen 2 to 3 thou or 0.07mm use a DTI on the end of crank and a pry bay to move the crank back and forth,a motor can run all the bearings without end float and i have seen engine rebuilders forget to check for end float.
Give it a tap on the caps and crank with a rawhide-copper hammer to help with end float if you cant get enough.
The crank should spin nice an free without exception,like you should be able to spin the crank and it should do a couple revolutions under its own momentum.
Not to put the scares up you but i really do suggest you under drive the oil pump and reroute the oil pressure to feed the mains directly,our ground undersized crank only lasted a couple of race meetings before it destroyed itself.
Ive started modding the gear and oil pump for this and will post up some picks soon.
OH and heres a good one,the low k bottom end i got recently which is in mint condition(75,000ks) i pulled down and the crank is bent,now this is the second motor ive pulled down that had mint bearings and the crank is bent almost 15 thou.
Im thinking this may be a manufacturing fault and under normal operating conditions the crank would probably last a long time but as soon as some boost is cranked though it the bottom end fails because of this.
i wish i could get some good quality undersize bearings!!!!!(not NDC Rubbish)
Check for any unusal marks on your bigends from high spots like scratches etc.
put it all back together and check your end float- should be betwwen 2 to 3 thou or 0.07mm use a DTI on the end of crank and a pry bay to move the crank back and forth,a motor can run all the bearings without end float and i have seen engine rebuilders forget to check for end float.
Give it a tap on the caps and crank with a rawhide-copper hammer to help with end float if you cant get enough.
The crank should spin nice an free without exception,like you should be able to spin the crank and it should do a couple revolutions under its own momentum.
Not to put the scares up you but i really do suggest you under drive the oil pump and reroute the oil pressure to feed the mains directly,our ground undersized crank only lasted a couple of race meetings before it destroyed itself.
Ive started modding the gear and oil pump for this and will post up some picks soon.
OH and heres a good one,the low k bottom end i got recently which is in mint condition(75,000ks) i pulled down and the crank is bent,now this is the second motor ive pulled down that had mint bearings and the crank is bent almost 15 thou.
Im thinking this may be a manufacturing fault and under normal operating conditions the crank would probably last a long time but as soon as some boost is cranked though it the bottom end fails because of this.
i wish i could get some good quality undersize bearings!!!!!(not NDC Rubbish)
Re: Question for VH the rebuilders...
Thanks holset. I took it back to the machinist so he can get it right, since I payed him to do so. I'll look into the oiling issues, I did however have the machinist enlarge the oil drain backs in the head & block, moly coated the piston skirts, rod & main bearings. I also polished the sides of the rods.
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ThePhoenix
- Posts: 6
- Joined: Sun Jun 28, 2009 2:55 am
Re: Question for VH the rebuilders...
Holeset
When you say re-route the oil pressure, is this putting the line into the front of the block, just under the water pump? You wouldn't happen to be able to post/send any pics could you?
Thanks
When you say re-route the oil pressure, is this putting the line into the front of the block, just under the water pump? You wouldn't happen to be able to post/send any pics could you?
Thanks