LD32 Engine build

[jonbills]

I have to say, I felt the same about my new engine, especially during the running in period when I was constantly out in it. Then after a winter layup, you get into it and it makes you grin large!

Which rad are you getting? An eBay aluminium one perchance?

I wonder if the engine mounts have more longitudinal movement than anticipated? Come on, how hard were you braking

yeah this one. https://www.ebay.co.uk/itm/363012511881

That's an interesting thought about longitudinal movement, there must be some! but I hardly used the brakes on that run. ¯\_(ツ)_/¯

 

[Rob Gaskin]

Jon as I mentioned on the other Thread re Viscous/electric I've had a fan hit the rad. Partly due to heavy braking on track (Mallory Hairpin) high revs and soft/cracked blades.

Will your fan be balanced now?

 

[Mark N]

Does the dimensions of the diesel water pump or front cover move the fan forward towards the radiator compared to the petrol set-up?

 

[jonbills]

Jon as I mentioned on the other Thread re Viscous/electric I've had a fan hit the rad. Partly due to heavy braking on track (Mallory Hairpin) high revs and soft/cracked blades.

Will your fan be balanced now?

I suppose with high speed corners you're going to have some flexing of the blades from precession. The balance of the fan will be different, but I did try to cut each blade the same. Time will tell if its a problem.

 

[jonbills]

Does the dimensions of the diesel water pump or front cover move the fan forward towards the radiator compared to the petrol set-up?

I don't think so, but I didn't measure. It was always close to the rad on the previous engine, I think the difference here is that the the fan has moved down to overlap the bottom tank, whereas before I think the fan was exclusively in line with the matrix.

 

[jonbills]

I don't think so, but I didn't measure. It was always close to the rad on the previous engine, I think the difference here is that the the fan has moved down to overlap the bottom tank, whereas before I think the fan was exclusively in line with the matrix.

thinking about this more, the front crank seal must be in the same position for both engines for the cranks to be interchangeable, that determines the position of the crank pulley, which in turn determines where the water pump pulley is, so I think the diesel timing cover and water pump must be the same depth as the petrol ones.

 

[AliK]

Interesting discussion on this JB. On mine, the fan overlaps the top tank more thank I imagined it should but it's a good 3 cm away from the matrix. Then again, mine has a stock width radiator on so with your 3 or 4 core rad, you probably have pushed the limits of clearance tighter.

 

[Rob Gaskin]

FWIW I'd fit an electric pusher and stop worrying. Maybe cut your mechanical fan to half size for a gentle draught which 90% of the time will be enough.

Radical but then you are Jon.

 

[AliK]

Radical but then you are Jon.

 

[Woody928]

Sorry to hear that chap! I really sympathise as I did exactly the same thing to a brand spanking new Mishimoto rad, we took out 4 cores and its now only good for wall art in my garage...

Our theory was that with the new super lightweight flywheel the engine could rev that much faster that the fan flexed under the stress which caused it to move far enough out and wreck the rad. Could be a similar story given how light all the internals are in yours now and the silly high rpm's that it can reach! Another reason as to why I have electric spal fans fitted to mine instead.

 

[jonbills]

Interesting discussion on this JB. On mine, the fan overlaps the top tank more thank I imagined it should but it's a good 3 cm away from the matrix. Then again, mine has a stock width radiator on so with your 3 or 4 core rad, you probably have pushed the limits of clearance tighter.

yeah with the standard rad, there's acres of room between the rad and the fan, in fact I can even get a socket on the crank pulley with the standard rad!
I've been running little spacers (actually, exhaust washers!) between the rad and the panel to make room for the air sealing, with the new rad I'll take the spacers out. Hopefully that and the cropped fan blades will keep me safe.

 

[jonbills]

FWIW I'd fit an electric pusher and stop worrying. Maybe cut your mechanical fan to half size for a gentle draught which 90% of the time will be enough.

Radical but then you are Jon.

I'd then have to worry about the electric fans not working!

 

[AliK]

I'd then have to worry about the electric fans not working!

Exactly my reason for running both mech fan and pusher fans at the front. That way I worry less and have the option to switch on extra cooling if needed.

Sound like with spacers taken out and cropped blades you will be OK now. Would be interesting to track how much cooling you’ve lost.

Having said that, I had an incident where my fan blade cut into the shroud which stopped the fan going round, I drove another 10 miles (not realising what that noise had been and putting it down to a stone chip of sorts). The temp gauge was pretty normal all the way home. I guess you get lots of air flow when moving over 30mph and the fan really comes into it’s own when you’re going slow or stationary.

 

[Rob Gaskin]

I'd then have to worry about the electric fans not working!

If you are paranoid about electrical things not working why is your engine bay full of them?

 

[jonbills]

If you are paranoid about electrical things not working why is your engine bay full of them?

I swapped my viscous fan for electric fans a few years ago (well, probably 10 actually!) and the fuse blew a few times leading to overheating. I think my fusebox was really the problem, but the fact is that viscous fans fails safe, electric fans don't, and the electric fans weren't 'better' in any other practical sense. So I swapped back to viscous and have kept it since. I would go electric back to electric fans if this doesn't work out.

 

[johnymd]

There are different depth fans. Cant remember which way around it is. Ill dig out the numerous viscous units and fans to see the differences. I destroyed the rad in my ratty car a couple of weeks ago. Maybe I used the wrong fan.

 

[Alphabettispaghetti]

what about getting a mteal bladed viscous fan, they'll be next to zero flex in that.

 

[jonbills]

what about getting a meal bladed viscous fan, they'll be next to zero flex in that.

I need to retain originality

 

[Alphabettispaghetti]

I need to retain originality

A nice early car fan

 

[jonbills]

There are different depth fans. Cant remember which way around it is. Ill dig out the numerous viscous units and fans to see the differences. I destroyed the rad in my ratty car a couple of weeks ago. Maybe I used the wrong fan.

Thanks John, would be good to know the options.
I think I tried a 280zx fan, or maybe a 280zx viscous clutch once. Whichever it was, was too deep and the fan hit the rad.