924 Turbo

November 2014
I wasn’t really looking for another project but I had been toying with the idea of one day picking up a front engine rear wheel drive vehicle like the old Ford Escort Mk II I used to have in the UK.  I have some RSS feeds set up and one of them brought a posting for a 1980 Porsche 924 Turbo to my attention.  The good parts are that it is front engine rear wheel drive with a manual gearbox, it’s in decent shape and should have the awesome Porsche handling.  On the down side, it has been off the road for 17 years, it doesn’t run (no power to the fuel pumps), there are lots of electrical accessories not working, and it’s purple!

I apologise for these bad pictures, it is winter so I’ll have to wait for spring to update with some better ones.

As Received 1  As Received 2

And at long last, here are some slightly better pics,

OnRoad1  OnRoad2

To Do List

  • Replace cracked elbow on turbo
  • Replace waste-gate
  • Replace engine mounts
  • Replace damaged injector
  • Paint A arms and heat shields
  • Hardly any air coming from defrost vents, blower motor is not working
  • DS electric mirror not functioning and glass stained – stain covered with blind spot mirror
  • Driver’s seat cover repair

Completed Tasks

  • Replace damaged timing belt
  • Replace transaxle oil, 17mm allen key – Replaced with Lucas synthetic
  • Rubber hanger broken at cat – repaired with hose clamp
  • Exhaust split at muffler – new piece welded in
  • Engine tapping – adjusted valve screws, camshaft and followers replaced
  • Look at wrapping – Rick paid $3000 for the Dinero wrap
  • Repair paint damage – most areas filled, sanded and painted matte black
  • Safety inspection – only failed on fuel hose routing, holes in rear bumper??? and opening hatch – all passed
  • Replace rear speakers, install door speakers? – Installed Fiero seats with speakers in headrests and sub-woofer
  • Front alignment – CT
  • Replace tires – BFGoodrich gForce Sport Comp2 on interest free at CT
  • Grating sound coming from PS front wheel, bearing – bearings re-greased
  • Coughs and sputters over 3500rpm – checked for leaks in intake with smoke machine, all good, check fuel pump, fuel filter was clogged
  • Clean up rust on muffler and paint
  • Change oil and filter – moved oil pump housing round so that new filter fits – it worked!
  • Windscreen and headlight squirters not working – fixed old hoses, new one way valve
  • Speedometer not functioning – connected cable
  • Fix fuel level sender – and low fuel light, maybe?
  • Horn not working, again – bad connection at fuse (#1)
  • Check valve clearances – perhaps a touch tight?
  • Grease steering knuckle(s)
  • Repaired flasher relay
  • Parking brake light switch – made Fiero switch fit
  • Rear brakes – replaced rear pads, fixed parking brake cable
  • Rear speaker not working – re-wired and removed centre speaker
  • Changed spark plug wires
  • Radio not working – replaced with new
  • Exhaust hangers damaged – repaired/replaced
  • Tailpipe fallen off – welded Mustang tailpipe on
  • Need new battery – thanks again John
  • Fuse 7 keeps blowing – fixed short in seat belt warning lamp connector
  • Rear wiper has no power – refurbished motor
  • Fuel pumps not working – installed new pump, Walbro 255
  • Made seat brackets
  • Seats falling apart – replaced with tatty but comfy Type R seats
  • Driver’s seat sliders seized – new sliders $20!
  • Headlights don’t work – installed new lamps
  • Headlights don’t pop up


17 thoughts on “924 Turbo

  1. MTOAuth

    The head gasket failed!! On the way home from work it was boosting intermittently again. At an opportunity to open it up a bit, it boosted nice for a while before suddenly BLAMO – a big cloud of white smoke. Had to get towed home – must join CAA again since Fred stung me $130 to tow me less than 5K!!

  2. MTOAuth

    Removed the head and sure enough, the gasket was toast. Also there were a couple of gouges in the gasket face of the head, Dave J says that this is probably the cause of the head gasket failing – will have to get it skimmed.



  3. MTOAuth

    Found some marks on the cylinder walls that look like scoring but on closer inspection, I couldn’t feel anything to the touch and could not find any signs of debris (there’s a bit of oil in the pic that looks like debris) so I think they will be fine as they are.
    You can also see valve marks in the top of the piston, must have happened some time in the past – my timing belt was in tact.


  4. MTOAuth

    Had a good look at the camshaft and followers and found that they were badly worn. Took everything over to the fantastic Beatty and Woods in Mississauga who suggested replacing the camshaft and followers rather than re-grinding. The did a great job of skimming the head and while they had it, they did a leak check on the valves that came in within tolerance. Also picked up a head gasket set from Precision Auto, it’s for a NA 924 but the parts diagram gives the same part number for the Turbo.
    Struggled to find exhaust studs; CarQuest came through with some in the end for under a buck each – nice.



  5. MTOAuth

    Found a used camshaft in UK at porsche924.co.uk, only 8000 miles on it. No followers but I contacted the guy and he had a spare set that he agreed to sell me with the camshaft. Got a great deal with reasonable shipping and the guy did a fantastic job of packing it all so it arrived safe. Had to do a bit of fiddling around to get the clearances in and a couple of valves are close to the limits of adjustment.
    Once the camshaft was all set, Josh helped me install the head re-using the same bolts. I did a lot of digging and found that the head bolts changed in 1980, the newer ones are polygonal (like a 12 pt socket) but mine are the old hexagonal ones (like a regular 6 pt) that are not Torque To Yield and look in great condition.
    Next up, timing belt and inlet.

  6. MTOAuth

    Took an age to find information on the torque setting for the timing belt tensioner bolt, in the end I went with the 33 ft lbs requirement that is used on the 944.
    Once the exhaust was all connected up to the head again, it was ready for the inlet. Jake came out and helped clean up the inlet before we installed it. Need to have a good look round and check that everything that needs to be connected is in place while at the same time trying to avoid installing anything that will be in the way later. Then we can move on to the fuel injection system.

  7. MTOAuth

    Started putting the fuel injection back on but dropped a bloody copper washer down the back of the head that didn’t make it to the floor and another slid behind the washer fluid tank! Replaced with fibre washers and finally got the two lines connected at the back of the head. After connecting the line at the back of the intake I noticed a crack in one of the elbows on a diaphragm in the vacuum system. Need to replace that obviously, wondered if that might have been why it wasn’t getting boost sometimes? Surprised I didn’t see anything with the smoke machine.



  8. MTOAuth

    Struggled to find an elbow so I made one up out of a plastic elbow with rubber hose in each end, it should be alright for now. Then I could finish off installing the fuel injection and vacuum system and put back the alternator and air box. Everything went fairly smoothly, had to repair a couple of broken wires, but I could not get it started – it was firing but would not run. After digging around I found that I had forgotten to tighten the injectors!! Now it is running nice but it is smoking like crazy and it stinks of coolant.
    Last night I had a look round for external leaks and couldn’t see anything so I took off the valve cover and re-torqued the head bolts. They were on the low side of the tolerance but in range, tightened them to the cold setting of 86 ft lbs. Will fire it up again this weekend and see how it goes.

  9. MTOAuth

    Just before the weekend my wife let the truck run low on coolant and overheat! Obviously it’s up to me to keep an eye on the coolant level and in this case I failed. Even the odometer beeped and flashed up “Check Gauges” to tell her to look at the temperature. Anyway after I topped up the coolant I couldn’t find any signs of a leak and started getting concerned about a blown head gasket. My buddy in the UK suggested I get a block check kit and with the 924T blowing smoke as well I figured it would be a good investment. Unfortunately the guy at Car Quest had never heard of such a gadget??? Sometimes I wonder if people struggle with the accent and then just play dumb. The guy at Napa knew exactly what I was after but had to order one, finally Canadian Tire came through and with a good price.
    This gadget consists of a tube, a rubber bulb and some fluid. You put some of the blue fluid in the tube, place the tube over the radiator or overflow tank cap with the engine warm and running and then draw air through the fluid by squeezing and releasing the bulb – if there are any combustion gases in the air, the fluid turns green.
    Good news everyone! Checked the F150 and the 924T and the fluid stayed blue the whole time – see pic.

  10. MTOAuth

    The trim around the heater controls is cracked and half of the tabs that hold it in place have snapped off. My dad and I spent a good bit of time searching for a replacement with no joy so I drew up a 3D model in Onshape with the intention of getting one 3D printed. The first attempt did not work well as there was a recessed face that required supports that left the face rough looking, so now I have split it into two parts that should print nicely ready for gluing. Just need to figure out a good way to get the markings on.

  11. MTOAuth

    Got under the car today to swap out the oil in the tranny with the new Lucas synthetic stuff I picked up yesterday. The stuff in the tranny has been there at least while it sat for the last 18 years and who knows how long before that, check out the state of it.
    After that I decided to clean, oil and fix up the throttle valves that have been sticking. After a bit of digging I traced the problem to an injection line that was running too close to the throttle mechanism on the underside of the intake. A bit of bending and tweaking and the throttle is now silky smooth, really looking forward to trying it out.

  12. MTOAuth

    Finally got the Porsche running and insured with classic car insurance through Hagerty. Went out for a run and it was stuttering and hesitating under load/boost. I remembered that last time it was doing that, it turned out to be the in-line fuel filter at the back getting clogged, so I checked it and found that the element had broken off allowing crap to go straight through into the pump. After installing a new one … exactly the same. Then I changed the metallic filter under the hood … exactly the same. Then as I was contemplating how to check the fuel system and injectors for blockages, my lad came out after a bit of googling and told me it was spark plugs. I didn’t think so but figured that they are easy to check so pulled them out … first one was black, other three were a nice tan colour. Swapped them out for new ones and now it runs great!! I know it’s lighter than the RX-8 or GTI but it pulls real strong now and feels like more than 150HP to me. Well done Josh, I’m happy!

  13. MTOAuth

    Ahhhh the joys of owning an old sports car! Driving along yesterday and it felt like it wasn’t pulling as strong above 4000rpm, opened it to 5500rpm and it felt like something kind of blew or something and then it was running like one cylinder wasn’t firing. Managed to crawl home and check the spark plugs with an in-line timing light, all looked good. Took them out and the one in #2 cylinder was black and wet while the others were brown. Installed new Champion copper plugs and it was exactly the same but when I took them out after 5 mins running, the two outer plugs were white and the two inner plugs were tanned – see pic.
    Cleaned up the old Platinum plugs and put them back in, then took out the injectors and cleaned them with WD40. Now I can’t even get it started!!
    I think it must be something to do with fuel, guess I’ll have to figure out a way to test the injectors and/or fuel pressure.

  14. MTOAuth

    Quite a bit gone on over the last few days, better get this updated. I found a huge tear in the lower vacuum hose going into the airbox from the EGR cannister behind the DS front wheel. Replaced that but it was still the same, ugh. I notced that the #1 spark plug gap was getting closed when the engine rotated, WTF? So I put the Champions back in, checked that they were ok and finally got it running. iI was running rough so we took it out to try and blast it out but heard something clatter and bang on the PS of the engine and down that side … and broke down. Managed to get it going on 2 or 3 cylinders and crawl home. When we got back Josh saw some oil on the drive that we traced to the elbow on the turbo waste-gate. Note: I haven’t heard the waste-gate going off before (but then I haven’t it on the GTI either), and the boost gauge has also reguarly been pinned at max. While checking the turbo elbow I found a nasty tear in the timing belt! Both the marks still lined up so nothing slipped at least, maybe that had something to do with the noise we heard ?? On with draining the coolant and and removing stuff to get to the timing belt. That’s it for now, more later on broken injectors and turbo elbows …

  15. MTOAuth

    Got a new timing belt from CarQuest, and got that installed ok. Took out the injectors and read up on how to back-flush them by pulling out the pin and holding it open with some wire looped round it. I got one done but it was very fiddly and difficult to do by myself, was going to go and get one of the kids to help but had one last go … and the pin cocked over and came out – that injector is now toast! Ordered new ones from AutoPartsWay along with an air filter, amazingly it all came the next day … and the parts were all wrong. The injectors were short and didn’t have a threaded section to go into the holder, and the air filter was a different shape – now we’ll see how easy returns to an on-line store are – I have to wait up to 72 hours for a response from a rep, that’s not a good start, I hope they have the right injectors for me.
    Started looking at how to get at the turbo elbow, apparently either the turbo or the water pump need to come off. At first I thought it would be easier to remove the water pump but since I have concerns over the waste-gate I might as well take the turbo off. I started following the workshop manual and taking my time, about ready to take off the muffler and then disconnect waste gate cable.

  16. MTOAuth

    Waste gate cable??? It’s a vacuum line from the rear of the charge tube – intake I’ve been calling it but it’s the part that goes from the turbo exit to the intake. Got the vacuum line off ok but all the nuts holding the J-pipe to the waste gate sheared off and the J-pipe just flat out refuses to come off. This J-pipe also prevents the main exhaust from sliding back far enough to clear the studs on the back of the turbo. OK I’ll remove the pipe on the back of the waste gate and slide the waste gate and J-pipe out together … one nut on the back sheared, another rounded and access to the remaining two is limited. Also the waste gate mounting bracket has snapped in half and I noticed that the stud sticking out of the PS engine mount has gone??
    So that’s where I’m stuck right now, sprayed a load of penetrating lube around the joint, trying to think of the best way to proceed.

  17. MTOAuth

    Decided to take Bernie’s advice and just cut the J-pipe, can always weld it back up again. So I managed to get the waste-gate and exhaust off and started looking at repairing the waste-gate studs. Then I dismantled the waste-gate actuator on top and found that the spring seems to have vibrated into the side-walls and gouged out grooves and the rubber boot has a tear in it – in summary, the whole waste-gate is toast. I imagine it will be tough to find another 924T waste-gate, in which case I’ll find one off something else with the same/similar boost setting (0.8 bar). Still need to get the turbo out to replace the cracked elbow.

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