How to test turbos?

Hi, I am rebuilding the engine of my 1992 VR4 which had oil starvation and subsequent main/bottom end bearing failure. As a result, there was a lot of metal in the oil. I am worried that some of the metal may have gotten in to the turbos and ruined them, and that the oil starvation may have damaged the turbos too. It would be annoying to put the engine back in the car only to find out that the turbos are bad and the have to remove the engine again. Does anyone know of a way to make sure the turbos are not damaged?

Hi Adam
You can buy a turbo overhaul kit for about £30/$40.
Given the problem that you had, I would rebuild the turbos anyway. Make sure that you also flush the oil cooler and oil pump because the crap will be hiding there for when you re-start the engine.


Hi, thanks Joe. Any recommendations?

The oil pump is very easy to dismantle and clean.
You can remove the cooler and run some engine cleaner through it.
The turbo repair kits are usually available on ebay but if you really struggle to get hold of one, I normally have a good supply.
Sooner or later, I will get round to doing a video for the kit but there are others online.
Beware of the shaft measurements for the turbo. I have only come across one shaft size myself but other people have reported two other sizes. Better to measure the size of shaft bearing before ordering a kit.

1 Like

Came across this during the week when I was researching oil pumps. Some good tips for installing the pump correctly. I was happy to see @Joe90 saying to flush out the pump and cooler as my engine was rebuilt just before I purchased and I was worried that the pump and cooler was not replaced. If flushing is good enough for Joe, its good enough for me.:+1:

On the turbos, if I ever need to remove my engine I will be upgrading the turbos to 13g’s ( I think that’s right) which bolt straight in and (I think) bring car to 360bhp.
They are expensive and are done on a swap around with your old turbos from Rob at EE. But that’s me, not advising you do do this, but I would deffo refurb while out especially the rear one.
I am getting a loud whistle or alarm sound while on boost sometimes, I’m hoping an air leak but someone suggested the waste gates can go weak and bleed air prematurely and cause this sound. Any ideas?

1 Like

Thanks for the help guys. I will order a pair of eBay turbo rebuild kits. I ordered an oil pump, input spool/output shaft and a set of head bolts from Ninja Performance in the US, so hopefully the project will be back on track soon. :+1: