Same question : And why, pray, might that be ?
Step By Step Engine Build, No Waffel, Just Building..
Posted 21 April 2017 - 12:09 PM
In fact the guys who build the high hp V8 engines clean the block and big end journals and the back of the bearing shells with lacquer thinners - prevents the possibility of the shells spinning in the journal. Of course one then puts oil on the inside of the bearing and the crank journal.
Posted 21 April 2017 - 01:02 PM
Exactly......sorry for not getting back to this sooner. You want maximum dry contact between the shell and the block or the shell and the rod. Putting a layer of oil in there acts like an insulator, and it's like adding a tiny layer of ball bearings between the shell and the block. I agree with cleaning them with lacqer thinner or such.......
Posted 06 May 2017 - 10:11 PM
This was a very careful and meticulous build, with good attention to detail, and there is much to be learned from it. However, there are two errors, one serious because it can wreck the engine, and has done so to others on many occasions. It has resulted in many other broken things too.
The serious one is the practice of centre punching bearing caps to identify them, in a place where the part gets into tension. That is a sure recipe for fatigue fracture. I would not use the services of any engine builder who was doing that. If you must centre punch a bearing cap, it must be on the outer side near the split between cap and rod, where the clamping action of the bolt holds it in permanent compression. It is preferable to use paint or something similar such as Tippex.
The other one is the use of copper grease on the clutch plunger. Copper grease is not for moving parts, and even worse, the combination of steel, copper and aluminium alloy in close proximity is going to be a corrosion trap. A long life, water repellent grease such as Molybentone could be used, or normal graphite grease. Plain old LM in an emergency.
Posted 01 July 2017 - 02:34 PM
great thread, one question, when refitting big end caps, you say that you can feel a difference if the cap is on the wrong way round.
I can't feel any appreciable difference. Is there another way to tell if they are the right way round? I.e. should the two small bent tabs on the big end shells be opposite each other, like side to side?
Posted 02 July 2017 - 06:49 AM
John, thanks for the reply.
I just want to be sure though, facing each other on the same side of the crank (i assume this is what you meant!)? Or facing each other across the diameter of the crank?
**edited, info found elsewhere on this most helpful forum. The tangs do indeed go adjacent to each other on the same side of the crank**
Edited by jonlad, 02 July 2017 - 07:37 AM.
Posted 04 February 2018 - 09:30 PM
Sorry I have not been on this site to answer any of your questions or to reply to any of your suggestions. As I have said on my other threads I do not profess to being a professional engine builder and have posted this thread as a simple guide to how I Have built these engines for my own use, They have now been in my minis for a few years and are performing very well, so far!!. Please do not take the information in this thread as gospel, Its simply how I do it. I'm sure as has been pointed out, that some of you do things differently, each to their own I guess. If a few of you have found the info useful them I'm happy that my efforts have not been for nothing. Please do your own research before simply following this guide. I would hate for any mistakes I may have made to be copied by anyone building an engine. However, I am reasonably confident that due to the miles I have put on these engines over the years that any mistakes I may have made are not to terrible.
Thanks again for your comments and suggestions, every day is a learning day for me.
Posted 26 April 2018 - 11:12 AM
Is anyone in a position to move the images somewhere else and update the links? I would be beyond grateful...
Posted 06 December 2018 - 07:49 PM
great thread, Do you not set the piston ring gaps?
Hi zeemax89. No I did not measure the piston ring gaps, probably should have done, but I didn't, The block was freshly bored to match the pistons that I supplied, I assumed that the guys at Precision engine services who did the bore work for me had measured everything for me. I know I should have checked it but I trust them implicitly as they have done loads of work for me in the past with no real issues.
However I agree completely with you that you should always check stuff as everyone can make a mistake. I know I have made a few as has been pointed out by a few of the comments in this thread. I am delighted that people with greater knowledge than myself have pointed out the errors. I just hope that no one has had any failures based on my advice.
1 user(s) are reading this topic
0 members, 1 guests, 0 anonymous users