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The Silver Buick's 1969 Firebird OHC six project.

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  • You will succeed...eventually... on both the editing, and the fuel starvation problems...
    Patrick & Tammy
    - Long Haulin' 2008, 2009, 2010, 2011, 2012, 2014...Addicting isn't it...??

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    • Well who ever called bad fuel pump wins. Despite it being purchased new earlier this year and only having three or so thousand miles on it, it is junk.

      Made it 70 miles before it quit on me. Hot wiring the pumps on and looking at the clear filters, it was obvious the feed to the pump had fuel and the low pressure pump was circulating fuel as I expected it to be. Pinching the return line to the gas tank still caused it to pressure up to 43psi, and de-pressurize when I let go. Strange. So I zip tied the known good pump from the Skylark (been on there since 2011 and has probably 25,000+ miles on it (2 Drag Weeks even at 4,000 miles round trip each), and moved the lines over and it fired up and made the next 405 miles without any fueling issues.


      (Oh, and always remember to put the car in park or set the parking brake! I pulled over there after coasting in neutral. I was under the car and it started to roll backwards on me! Yikes!)

      The crankcase vacuum behaves weirdly. I really would like to get a datalog of it to see under what parameters it pulls best, etc. I don't know if it's the PCV valve, rpm, piston ring seal, or what, but it seems to have a tough time pulling/maintaining vacuum below 3inHg, but as soon as it hits that 3inHg it pulls up to 6-10inHg fairly quickly and can hang onto that vacuum through a variety of driving conditions. What has confused me the most though is, it'll pull nice vacuum climbing a hill, but as soon as I start coasting down the other side the vacuum completely goes away. The intake manifold vacuum (pcv valve) is double digits and it doesn't seem to be able to pull a vacuum on the unloaded or nearly unloaded engine. Just seems strange. It pulls plenty of crankcase vacuum at idle, yet looses vacuum cresting and going down a hill.
      Last edited by TheSilverBuick; October 10, 2014, 12:04 AM.
      Escaped on a technicality.

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      • Could it be while engine brakeing it does not have as high cylinder pressure so the rings don't seal as well?
        http://www.bangshift.com/forum/forum...-consolidation
        1.54, 7.31 @ 94.14, 11.43 @ 118.95

        PB 60' 1.49
        ​​​​​​

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        • might look at how a pcv valve works, I think they close at high vacuum and low vacuum, and open at medium vacuum
          My fabulous web page

          "If it don't go, chrome it!" --Stroker McGurk

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          • Originally posted by squirrel View Post
            might look at how a pcv valve works, I think they close at high vacuum and low vacuum, and open at medium vacuum

            The more I drive it today the more I see that as likely. This nearer sea level air is AWESOME! It pulls a ton more vacuum too. I find I'm regularly sitting at a light, ~650'ish rpm and pulling over 15inHg in the intake, but the crankcase is barely registering anything, 4inHg tops, if that. I'll be playing with that some, possibly tomorrow morning.
            Escaped on a technicality.

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            • So yesterday morning I stopped by the local Home Depot and picked up a brass fitting with the same dimensions as the PCV valve and swapped it in. Now vacuum in the crankcase mimic's manifold vacuum to a tee (is there a pun in there?). I have not noticed any drivability or idle changes with the swap.

              I pull the vacuum through my catch can, so any oil drawn in should drop in the catch can's copper mesh "filter" I have in there, as well as using several baffles in the crank case to try and keep most the oil down. In the mean time though, I'm going to be closely watching my oil level for any changes. In "theory", under vacuum mist should drop out of suspension in the crankcase and overall mass transfer to the catch can should drop as well. I've noticed before, the more often the crankcase stayed under vacuum conditions the less oil and such accumulated in the catch can, the more often it was at atmospheric or pressure conditions the more oil would accumulate in the catch can.

              It also takes about 4 seconds after shut down for the crankcase vacuum to bleed off. I may start looking for a high flow check valve and look at possibly attempting making my own vacuum relief valve to keep vacuum below 6-8inHg. It does make me a tad nervous seeing 15+inHg in the crankcase. I keep waiting for it to suck the oil pan gasket in =P

              Also the dang electrical plug on the transmission has come loose. I'm not sure what even holds it into place, but it is dripping fluid and has a ton of play in the hole. So I guess I get to drop the trans pan when I get home.
              Escaped on a technicality.

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              • 200-4r? Case plug leaking? It has an o-ring and three of four "fingers" that hold it in the case. I have never found a used one that wasn't too brittle to be removed & reused.
                http://www.bangshift.com/forum/showt...n-block-wanted

                http://www.bangshift.com/forum/showt...-Blue-Turd(le)

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                • Yeah the case plug. I'll look into it when I get home. I tried some gentle pulling, pushing, etc to see if it would tighten up in the hole, but no dice.
                  Escaped on a technicality.

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                  • new connector (that fits in the case) costs about $5 from a transmission parts specialist. Get one, put a new o ring on it, and it should last for another 25 years.
                    Last edited by squirrel; October 12, 2014, 08:52 AM.
                    My fabulous web page

                    "If it don't go, chrome it!" --Stroker McGurk

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                    • I'm trying to remember if I got a new case plug with the rebuild kit.....I don't remember seeing one. Ordering one isn't much of a problem though.
                      Escaped on a technicality.

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                      • usually don't come with kits. And they will leak between the metal pins, and the plastic housing, when they get old. Similar to the TH400 connector, but different.
                        My fabulous web page

                        "If it don't go, chrome it!" --Stroker McGurk

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                        • Made the trip like a champ since the fuel pump swap. The oil consumption driving home was even acceptably low. I didn't add any in the 475 mile drive home, which the engine was sitting at basically 3,000rpm for the whole trip.

                          Heading to Vegas this morning. Traffic was very light, having left my Mom's house at 5:30am.


                          Here are the trip stats. I averaged 19.3mpg.



                          The next round of changes is a small update to the exhaust evac setup and then swapping out the rear axle for a 8.5" with a true limited slip differential.
                          Escaped on a technicality.

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                          • Groovy! Super glad you found the culprit and that you had a fix on hand. That's turning into a real car!

                            Dan

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                            • I'm going to paste this link right here.




                              (had to do the go forward a page, then back a page to find the thread.......)
                              Escaped on a technicality.

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                              • Swung into NAPA this morning and they exchanged my bad fuel pump for free
                                Escaped on a technicality.

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