5 replies to this topic

[Colakurt]

I am in the meddle of a complete rebuild of my engine and gearbox. I have stripped both the block and gearbox for all components except for the crankshaft, which I will probably also take out soon.

I know how to fix engines but a rebuild of this scale is a new to me. I have no doubt that I will get it all back together in working condition again, but I need some help with choosing what parts that should be replaced either for service or for best practice now that everything is out anyway. My main concern is nuts and bolts that should be replaced. I don't want to go cheap and miss replacing something important, but also don't want basically buy a whole new engine.

 

Due to existing issues I am already doing the following:

Replacing all gears and synchros in gearbox, plus bearings for drop gears and clutch release.

Replacing piston rings, douplex timing chaing and tensioner.

Replacing camshaft, cam followers and oil pump.

Replacing valve guides, valve stem oil seals and head gasket.

Clutch assembly is only one season old, so I will not be replacing that.

Cylinders look fine so I don't think a rebore/horning is needed.

 

Other than gaskets and bearings in the gearbox, crank and piston rods, what else should be replaced during a rebuild like this?

 

For further information, the engine is a top street tuned 1380cc which I guess the previous owner was driving hard.

 

 

[Icey]

Measure, measure, and measure again. You've not mentioned it in your list but without accurately measuring bores, journals, clearances etc.. you have no idea if you're spending money in the right places.

The couple of times I've rebuilt my engine, the thing the caused most problems wasn't what nuts and bolts I used (mostly reused factory if not chewed up/rusty) but assuming because something looked OK that it'd be OK. And don't be overly optimistic when measuring. If something is borderline out of tolerance, replace or rebuild it as it'll only bite you again later.

 

[Colakurt]

Of course, will be measuring the bores and valves and other parts to check for ware. 

[Lucas1988]

with what you've said you're replacing i would definitely be checking that the head is actually flat and thus may require a skim, i assume that your clutch assembly is fully balanced if not it'd certainly pay to have it so. Thinking on the spec of the camshaft, what was fitted to it and what are you changing it to, are you going like for like or going for something different? You've not mentioned about what you're running whether its dizzy or ecu ignition only or full injection system?

[nicklouse]

You want a list. Sorry you don’t know until you get measuring.  You might need a new block. The crank might need a grind. The block and head might need a skim. Actually as you are looking at changing the cam you might want to adjust the compression ratio to suit.

 

But all the fasteners are good to go again. They are not stretch bolts so as long at they are in good order they will be fine. Standard parts balanced will see 9k for short times. Also some of the fasteners available now are of interesting quality. 

[Colakurt]

The cam will be replaced from a Piper BP285 to a Minispares Evolution001. So going from a really fast road cam/rally cam to something more street minded. 

 

I know everything have to me measured to ensure correct functionality. What I was looking for was more if there was parts that is always replaced during a service, like the service manual suggests replacing the flywheel bolt and things like that.