Monday, August 28, 2006

More Pump Timing and Fuel Economy

Upon recommendation from a reputable source, I'm going to try timing SoDak at 0.95mm and let y'all know what I think. This is quite a bit higher that the 0.75mm spec and just a bit higher than the 0.92mm spec'd for non-US cars. the car's a bit lethargic at 0.75mm, in my humble opinion.

My friend bought the universal cam holding tool mentioned below. I timed the injection by rotating the cam sprocket and not moving the pump (a HUGE pain in the buttocks). First check your timing as described earlier in this BLOG. Next roll the engine over again to TDC, back it up until you get your lowest dial reading (should be zero from checking the timing). Then you loosen the rear cam sprocket, effectively disengaging the cam from the pump. If you want to add timing, say 0.2mm in my case, you roll the pump forward 0.2mm holding the cam sprocket (or use the cam holding tool). The camshaft will not move, only the sprocket. The rear sprocket has no woodruff key so it is free to rotate. Then you retighten the cam sprocket and recheck the timing. It's that simple. You need to make sure you don't turn the injection pump while you tighten the cam sprocket bolt, but you can just look at the dial indicator to make sure. Worked like a charm!

FYI the EPA fuel economy specs for the 1985 740TD w/auto are 25 city, 30 hwy. I get 30 hwy/city. It should improve with the 0.95mm setting.

Flat

Having never had a flat in my life, I had two this week, one one on the Jetta and one on SoDak. Now I always check the pressure in my spare tire when I check my other tires (I highly recommend you do this). The spare was great. The jack is the easiest of any I've ever used. There was, however, one small problem. No lug wrench. Aargh. All I had with me was a crescent wrench. Luckily I had my bike in the back and rode to the nearest repair station, left my wallet in exchange for a 17mm deep well 1/2" drive and I was on the road in no time flat (pun intended). Strangely, the valve stem had a tear in it!? That was kind of an odd flat, but better than having to plug the tire.

Lessons
  • Make sure you have ALL of your tool kit
  • Drive no more than absolutely necessary on a flat tire. You may be able to save it
  • Replace your valve stems when getting new tires

Sunday, August 20, 2006

Free Biodiesel Helpline!


You can thank my tax dollars for a free University of Minnesota Center for Diesel Research Biodiesel helpline. They will answer questions related to "biodiesel fuel use, storage, availability, or other questions." I haven't called yet, but here's the number 1-800-929-3437

Saturday, August 19, 2006

Another Trip to the Junk Yard


I returned to U-Pull-R parts in Rosemount to find a plethora of 7-series Volvos. I scored 3 14" Alloy wheels for $22 each. Very nice-no curb rash. I just need one more to make a summer set of wheels, but I can deal with swapping one tire.

It seems as if I missed out on a 240 turbo- a source of boost, Volts, etc. VDO gauges with Volvo printed on them. All the 740's had had their instrument clusters removed :( The turbo models have extra gauges that can be easily transplanted into my dash right above the fuel and temperature gauges, plus my clock has a busted plastic gear so I can't change the time.

There were quite a bit of interior pieces to be had, but none for the wagon. Better luck next time? I got the 740 part of the 740 GLE script for the rear liftgate. Anyone have the GLE?

Tuesday, August 15, 2006

Front Strut Inserts



It's finally time to do the front strut inserts. The struts have basically NO damping whatsoever. I went with Bilstein inserts. Around $50 wholesale. I'm off to put them in this afternoon! You'll need a spring compressor to do the job.

HA! You might also need an oxy/acetylene torch, an air hammer, a chain wrench, a pipe wrench and a LOT of patience. The nut that holds in the strut insert(picture above at right) is a bear to get off. I had to heat up the nut and strut housing and then airhammer it loose while hot. The threads will need some attention before the new struts go in.

Day 2.... Well the strut nut on the other side was a piece of cake. Some items that may need attention are the rubber bump stops (Volvo p/n 1273849). Mine had completely disintigrated. Also make sure you have both plastic accordian shock bellows (picture, Volvo p/n 1387735). I was missing one. All these parts delays are starting to get annoying, but I should have checked these thigns beforehand :/ There is a strut bearing (allows the strut to pivot against the vehicle body) that should be cleaned and repacked with bearing grease. It has a plastic casing, half yellow/orange, half gray, that can be easily pried apart to get at the bearings. (picture at right)

Day 3... Finally complete! FYI, this job can be done on the car. Disconnect the sway bar and tie rod end from the strut and the strut will then drop out of the wheel well. BE CAREFUL NOT TO STRESS THE BRAKE HOSES. Once the strut is free of the wheel well, use the spring compressor.

Sunday, August 13, 2006

Another Biodiesel Rant

So I have been getting myself all worked up about the fact that SoDak was still not starting well cold. It would chuggaluggakathunkathunkawaddadatablatatatatatatatatatatatatata and then run just fine. Alot of white smoke came out in the process. Turns out the batch of batch of biodiesel I had was at fault. 1/2 a tank of petro diesel and she's starting perfectly cold. In addition, the VW Jetta TDI was running sluggishly. A couple gallons of pertro diesel and she's MUCH more peppy. I don't know what these morons are doing. Get the kinks worked out before you subject us all to your sophomoric chemistry experiments. University of Minnesota professor Dr. David Kittelson recommended that I run a max of B20. I'm inclined to follow his recommendations to avoid future problems. As much as this pains me, unless you're making B100 yourself, I'd recommend following his advice as well.

Saturday, August 12, 2006

A few notes on pump R&R and Smoke

After seeing a VW 1.8T timing belt that had almost shredded itself due to a bad water pump sprocket bushing, the importance of lining up the pump sprocket and the camshaft sprocket comes to mind. Line up a straight-edge with the camshaft sprocket. it should line up perfectly with the pump sprocket. This is only really necessary if you remove the pump mounting bracket or if your rear belt seems to be wearing prematurely/unevenly.

Regarding the smoke... I seem unable to get the Volvo to smoke even if I mash down the throttle and am running petro diesel. This is a good thing. It might be due to the new pump timing setting (0.75mm), injector recalibration (155 bar) or the rebuilt pump or a combination of the former. Whatever it is, it's good news.

Monday, August 07, 2006

Pump Timing Values & Return Lines


It turns out that I mistakedly set my pump timing to 0.44mm instead of the 0.75mm specified by Volvo for engines with an EGR system. This caused a bit of hard starting/rough running cold. The also increased cranking time when warm. I used to be able to just blip the key and she'd start. At 0.44mm, it would take a bit longer. there have been lots of numbers thrown around as to what the pump should be set to, anywhere from 0.72m to 0.95mm. Which one should you use??? According to Volvo Supplement to Manual 30571/1, the pump should be set to 0.75mm for all cars equipped with an EGR system. Unfortunately my car might be missing some of the EGR system (??) so I'm not sure if I should still use this value... Manual 30571/1 gives the following values:

D24T Exc. USA/Canada 0.9mm
D24T USA/Canada '82-'83 0.8mm
D24T USA Federal/Canada '84- 0.85mm
D24T USA Calif. '84 0.75mm

If it wasn't such a pain to retime the pump, I would try a spread of values and post some feedback :/ BUT, I found this on a Dodge Ram website

Advancing the timing will...
  • Decrease exhaust temperature
  • Increase cylinder temperatures/pressures
  • Increase fuel economy
  • Increase your output of NOx
  • Decrease your output of Hydrocarbons
  • Increase the amount of black smoke at peak torque


FYI, the cold start device, when operating correctly, should increase the above measurements by 0.20-0.25mm. This gives you a quantitative test for you cold start mechanism.

I have started selling 1/8" I.D. X 1/4" O.D. biodiesel-compatible fuel line. It's more heat resistant than Tygon and has the perfect degree of flexibility. The plastic hose I put on after the pump rebuild cracked and dumped fuel down the side of the engine so polyethylene(translucent plastic) fuel line is definitely not a good idea for this application. At $3 a foot, it's 1/2 the cost of Viton and it comes in a cool translucent bright yellow color. You may send $$ for as many feet as you'd like + $4.05 USPS Priority shipping to mycoleptodiscus@yahoo.com via Paypal or email me for my home address to mail me a personal check.

Friday, August 04, 2006

We're Rolling!

After reinstalling the injectors and pump, it was time to prime the fuel system. I replaced the fuel filter (necessary if you ever need to claim any sort of warranty for your rebuilt pump) and applied a vacuum (evacuated freon container with air removed using a vacuum pump) to the pump return line (because it's at the top of th efuel system and any air will accumulate there) and pulled fuel SLOWLY through the system. I then cracked the injector lines at the injectors and turned the starter over a few times to get the air out of the injector lines. Yes, it's a little messy, but necessary. Started right up! Did throttle adjustments according to the manual and my idle is a bit high. More adjustments will come later. I guess the important thing is, after dropping $680, SoDak should be good for another 100,000 miles.

The interesting thing was that the three bolts that hold the pump bracket to the engine are responsible for adjusting the rear belt tension. After seeing firsthand the pump bushings worn on one side- the importance of proper belt tension comes to mind. Tension gauges are now on Ebay from ZDMak

I also learned that replacing the pump is actually really easy! If you can adjust the pump timing, you can do the pump. Speaking of pump timing, the timing tools bought from Germany actually work great- no problems. The other thing is that, unlike the front timing belt, if you screw up the job, you can't destroy your motor :)

Another thought- I am considering adding an intercooler. I have been looking at th eturbo piping from a "classic" SAAB 900 and it has a nice cast aluminum 90 deg. bend piece that might work perfectly... More later.