7 replies to this topic

[NDT]

Planning to rebuild the engine next week.
Worth fitting new core plugs? Block will be getting painted next weekend too.

[NDT]

The current ones look ok - just wondered if it was a standard thing to do.

Edited by NDT, 16 May 2020 - 04:39 PM.

[Thelowrider]

I'd replace them personally whether they look okay or not for the sake of a few quid means you can paint the block remove them then fit shiny new ones

[nicklouse]

these looked ok

 

[Spider]

Just to take another step back here.

 

I always pull the plugs on every build. Not just for the sake of replacing them, but most importantly, I send the block off for acid cleaning. The main reason for this is to clean all the crud and in particular, the rust from inside the cooling jacket. Rust is a very poor thermal conductor. They say a 1 mm layer of rusted steel or iron has the same thermal conductivity as around 16 - 20 mm of steel plate. A high majority of engines I've seen over the years that have run hot or over heated are because the blocks cooling jacket is rusted up.

 

I wouldn't dream of doing any engine build without having this done.

 

Pulling the plugs allows this process to be more thorough and also makes it easier to monitor. 

[NDT]

Very helpful - thanks guys.
Might be a stupid question... do I need to pull out the cam bearings if I’m getting the block dipped?
Worth getting the transmission case done too? Obviously there’s only oil residue in the that.

[Spider]

Yes, you'll need to pull the Cam Bearings.

 

I'd also suggest pulling the Main Oil Gallery Plugs and the Oil Pressure Relief Valve Seat too, but many have built engines without pulling these for cleaning and say they've not had issues. I like to pull them not only for cleaning, but you can also look in them and see they are clean.

[MCCS.Eng]

Great to read this thread. I work for a small machine shop. They have their own chemical baths etc and it is nice to see good advice being passed around. The guys doing the block prep here always say it’s good to have as many windows into the block as possible so they pull everything. Carry out the prep then dip, machine and put it back through the prep and cleaning processes before painting and then giving a final clean.

They also tell me that the majority of your time spent on any build, be that reconditioned road or a full scale race engine will be in the preparing and cleaning.

I just build their website and paint things though hah