180 Turbo Blues

[jeffinpa]

Finally got the 180 and four speed installed in the 65 Monza Convt. The car starts and idles fine. The vacuum/pressure gauge sticks on the vacuum side, so I can't really tell if it's making boost or not, but think it's not, because of the exhaust leaks. (the #3 tube needs replaced, and something is leaking on the left side, too.) Anyway, I can drive around the neighborhood and into town with no issues. I initially had problems with it losing power when hot, but found out that the YH carb was actually flooding (I thought it was too lean), but a fuel pressure regulator fixed that. Last week, i was getting on it uphill to see if it would make boost, and it overheated. The overtemp switch is new. The thermistor is inoperative, so I don't know the real head temp. I checked the ignition timing, and set it 24 degrees BTDC like the book says. I also found out that the distributor has a vacuum advance instead of a pressure retard, so I reset the timing with the vacuum line plugged. When I drove the car for about half an hour (plenty of time to warm up) it ran fine. I took it out on the highway and opened it up, and it overheated again within a mile or so. Let it cool, drove home with no more overtemp. It doesn't ping-ever, so I'm not concerned about the pressure retard, but why does it overtemp when I get on it? The shrouds are all there, the lower sheet metal for the thermostats is removed, and it gets hot when I push it. Any Ideas?

[notched]

How are you monitoring temperature is the thermistor is inoperative? I would be very skeptical with just the light. Do you have any gauges to monitor oil temp or anything along those lines?

[flat6_musik]

Agreed. If it's not pinging, it's not overheating. I would NOT go into the turbo boost until you get the pressure retard right. If the initial timing is set at 24 with no boost retard, that's a recipe for destruction.

[notched]

Where in Pennsylvania are you located?

[miniman82]

Last week i was getting on it uphill to see if it would make boost, and it overheated....It doesn't ping-ever, so I'm not concerned about the (lack of) pressure retard...

Speaking from lots of experience with air cooled turbocharged engines, you're making contradictory statements here.


Your engine is trying to tell you something is wrong, but you're not listening. The fact that you don't have a pressure retard means you have no way of backing off the timing when manifold pressure rises, and if the turbo really is working like it's supposed to I can assure you it most certainly IS detonating. Maybe you're just not hearing it? Here's the problem: with any other distributor but what a 180 is supposed to have, you're going to end up with too much timing nearly all of the time. This is normally not a problem with low loads on the engine as you've pointed out, but when you ask it to make power it refuses and only gives you really hot heads (and in the longer term melted aluminum for you to hang in your garage).

Stop trying to make boost or drive at WOT in your car until you address the timing issues, or broken parts will be your engines gift to you. Once you're sure the boost retard is working (good luck finding a retard can that actually does what it's supposed to BTW, and you BETTER check with a timing light and a source of pressure before you attempt power runs!), then you can move on to making sure the fuel mixture is also correct. This involves use of a wideband oxygen sensor in the downpipe, so you can see what it's actually doing instead of guessing.

You might think I'm blowing smoke and you really won't like the cost of getting the timing and mixture sorted, but that's what is required to drive these engines with any sort of reliability expectation. You can't simply plug parts into it and expect good things to happen, you have to tune it and that also means knowing how to tune.

[855r]

Sorry to hear of your troubles, like suggested above if you have malfunctioning/broken ignition retard parts you have to get that fixed and sorted out. I would consider picking up a cheap boost gauge and running a length of vac line to a port or some vacuum/boost signal and have that gauge just sitting on the passenger seat or your lap if need be. This way you'll know what's going on at least when your figuring this out. It also may sound like a pain but you may want to take the top shroud off which means carb/turbo ect all of that and make sure you don't have a bunch of debris blocking the air flow from your fan. That would make a good time to de-burr the cylinder fins to maximize the air flow too. I did it to mine while the engine was already out and it did make a big difference. I'd hate to see your next post about how you put a hole in one or more of your pistons or something.

If your budget will allow this is what I did when my advance/retard can went bad and a replacement was B/O from Clarks for months. I converted my distributor to a pertronix style ignition (mines actually a crane XR700) I installed a used working MSD 5AL box I had and picked up a MSD Boost timing master. Not exactly cheap but very reliable and accurate now. I can dial 0-3-1/2 degrees of retard per LB of boost and set when it starts to pull timing. My current set up is driving pretty good at 24 degrees initial with a custom mechanical advance, 2 degrees of pull per psi, starting at 3 psi. my wastegate is shimmed to 13 LBS now so I am pulling 2 X 10 or 20 degrees at full boost. I see 13 lbs in every gear with my Weber, E-Flow intake, B flow crown exhaust housing and 2-1/2" downpipe. If I do hear a telltale sign of detonation I will give it more timing pull per LB of boost.

[frez]

Hi guys
Related to this topic on my car my cylinder head gauge will be at 200-400 or so operating but after about 10-15 mins of driving highway or around town the needle buries over the 600 mark. My shrouds are failed open. I have new thermometers on order as well as a new advance/retard bulb all from clarks. Based on all I have read on posts I will clean or replace my oil cooler do a tune up and adjust timing to 24-28. Aside from all that is it possible I am running that hot without any lights or buzzers coming on? What is the ping that is referenced in these posts?

[cad-kid]

One diagnostic tool Frez is to use an infrared thermometer and aim it at the cylinder barrels (compare left & right sides). Also pull the top cover (aka turkey roaster) and check for debris on top of the cylinders.

[frez]

Thanks, pulling the top cover is a hell of task in a turbo. I have to remove the turbo first right?

[cad-kid]

I'm not really sure on that. You should be able to eye ball it though and determine what will need removal (sorry)

[notched]

Yes the turbo has to be removed.

[jeffinpa]

Hey all,
Thanks for all the replies. Sorry I haven't replied myself, but work gets in the way. Anyway, yesterday was a fairly cool day here in south-central PA, so I disconnected the vac/press line to the distributor and connected it to a test gauge that shows vac/press. Going downhill with the throttle cosed, I'm pulling about 15-20 in of vacuum. Going uphill, wide open in third and fourth (where boost should be maximum) the gauge shows zero to 1/2 psi of pressure. Mind you, the static reading(without being connected to anything) is 1/2 to 0, so, effectively I've got NO boost at all. I hope this is due to the exhaust leaks (both number 6 and number 3 have leaks -number 3 needs a tube, and I haven't removed the manifold from number six yet.

I have ordered an advance/retard unit from Clarks, but I have more questions- mainly, is the turbo distributor different than the others? By that I mean is the centrifugal advance different? Or does it even have a centrifugal advance?

Thanks in advance, you guys are the best!

[jeffinpa]

OOPS! I meant to say the exhaust leaks are on number 5 and 6

[thewolfe]

Yes the turbo engine has a special distributor. It doesn't start advancing until around 4000 rpms. If you have any exhaust leaks before the turbo it will totally kill your boost.

[notched]

65-66 turbo distributor part# ends in 329 on the distributor body.
You really need to fix all exhaust leaks before going any further.

[jeffinpa]

Sorry it's been a while, but it took a while to sort the troubles. Exhaust leaks- need all six exhaust tubes (all were rusty/leaking, and a crossover pipe.
Also needed all six pushrod tubes on the left side,they were leaking due to, you guessed it-rust. So, no more exhaust leaks, no more oil leaks. And installed a thermistor, so temp gauge works now. Haven't tried it at high speeds/ boost, but it seems that temp is still high. Cruising at 46 mph, temp is reading around 400 degrees. Boost gauge brely moves in either direction, shows a little above 0 at WIOT, so it looks like turbo checkout is next-after the harmonic balancer, which is showing some deterioration. The fun never ends!