Turbo technical - 2L-T

[thestoredt]

Hi Guys,

Need some troubleshooting advice for my turbo.

Since I've had the '88 surf - 2L-T engine early type with tappets, the turbo light has never worked, although once in a blue moon it's lit up for a few seconds.

I'm guessing a wiring fault or swithc fault, wondered what the best plan of attack is to detect the fault?

[surfenstein]

Hi Guys,

Need some troubleshooting advice for my turbo.

Since I've had the '88 surf - 2L-T engine early type with tappets, the turbo light has never worked, although once in a blue moon it's lit up for a few seconds.

I'm guessing a wiring fault or swithc fault, wondered what the best plan of attack is to detect the fault?

The light will only work when on boost, so my first point of call would be to the boost pressure sender.

[thestoredt]

The light will only work when on boost, so my first point of call would be to the boost pressure sender.

Surfenstein,

Now the engine's fully rebuilt, the turbo light still isn't activating.

If the engines warmed up, if I push the small diaphragm rod and open the diaphragm by hand, the engine revs higher, and the turbo light kicks in when i open the throttle.

Is it activated by vacuum or is there something that should be pushing on this rod?

[surfenstein]

The engine needs to be under load it won't work stuck on the driveway revving the nuts off of it.I take it you are on about the boost actuator arm on the turbo.

[thestoredt]

I've replaced all the vacuum hoses and driven it from Southampton to Matchams and had a day out there. The turbo green light comes on for short periods whether under load or not, but I can feel the difference in pull when its on.

The diaphragm I'm talking to is next to the fuel pump. It's a horizontal arm that pushes into a vertical diaphragm that has a vacuum hose linking to the t-piece that goes to the pressure switches.

The photo attached isn't mine as the arm doesn't connect to the lever where the arrow is is the same apart from that

[tweak'e]

that diaphragm/acuator is an idle up, ie aircon idle up.

but the interesting thing is its not a turbo injection pump, its a pump for an atmo engine. either someones replaced the pump or its an atmo engine with turbo gear bolted on.
my guess here is its under fueling by a fair amount which may be why you do not get much boost. imho don't worry about green light, fit a boost gauge and see what its actually doing.

got any pics of the rest of the engine? just to see if anything else has been changed.

[surfenstein]

The boost control is missing from the pump.looks like the pump is from a naturally aspirated 2L engine .Or has someone just bolted a turbo on the side of a 2L engine. Just like Tweak'e said.lol.

[thestoredt]

It wasn't my actual pump just a pic off the net to demonstrate where the diaphragm is. I'll take a pic of my setup over the weekend and post it up

[thestoredt]

My actual motor

[surfenstein]

I would still check the boost pressure switch and also the boost compensator diaphram for a pin hole.If in doubt fit a boost gauge,that should tell you what the engine is boosting at.

[thestoredt]

Boost gauge ordered - where does it tee in to the vacuum hose? Near the pressure sender switch?

Not sure how to change the fuel delivery if the boost and 'phragm are ok.

Also - the sensor that's normally in the intake pipe between the airbox and "the hose is not missing and I have the wire disconnected.

What is that sensor for? I've replaced the hose etc. to ensure there's no loss of air pressure in the intake.

[thestoredt]

So......For anyone that's interested it was the vsv valve seized and blocked. Cleaned and replaced filter. Turbo works fine. Replaced all vacuum hoses and runs like new now. Heading over Salisbury Plains for a jolly on Sunday! Pics to follow

[WannaSurf]

I am having the same issue, which VSV was the problem. Any chance you still have photos that you could post?