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PCV Job and Alternator 850

posted by  someone claiming to be Margaret on  Mon May 4 03:47 CST 2009 [RELATED]

I am going to dive into the PCV job next week on my 1994 non turbo 850. While I have it apart, is there anything else I should do? Should I replace the knock sensor even if the current one is still good. Also, I am going to put a new belt on as well. Should I change out the alternator or anything else while I'm doing it? Is there something I should check before I do the PCV job? I have oil leaking from the oil cap and the dipstick blows out. The car has 185,000 miles on it and I want to drive it to at least 300K. Let me know your thoughts please.

Margaret








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    PCV Job and Alternator 850

    posted by  tom 240 on  Mon May 4 18:52 CST 2009
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    last visit: Wed Jun 17 18:20 CST 2009
    [RELATED]

    Hi,
    I would leave the knock sensors and altenator but renew the voltage regulator if still original as the brushes wear out anyway and cost is about 30USD only.

    Cleaning the block and compartment is time consuming but is a joy afterwards for a long time.

    br Tapsa








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    PCV Job and Alternator 850

    posted by  KlausC on  Mon May 4 17:07 CST 2009
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    last visit: Fri Oct 24 10:15 CST 2014
    [RELATED]

    Doing the oil separator and the Tbelt are 2 different jobs, treat them as such. No, if the knock sensors are OK then leave them alone. Make sure the screen is gone at the PCV valve and clean out the hole in the block that connects the oil sep box.

    When doing the Tbelt, check the water pump for play or weeping and all of the rollers. The tensioner should be good, but the tensioner roller probably should be replaced.
    --
    My name is Klaus and I am a V ♂ lv ♂ holic.








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    PCV Job and Alternator 850

    posted by  jadnhm on  Mon May 4 05:25 CST 2009
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    last visit: Tue May 22 18:03 CST 2012
    [RELATED]

    Last time I checked (last week) the local NAPA wanted $500 for a new alternator. I wouldn't recommend doing it pre-emptively. If you're concerned at all, take it out and have it tested/checked at a real starter/alt place. They can pull it apart and test the individual components and tell you how the bearings feel and how things are wearing inside. I recently ruined an OEM bosch unit (oil), and the guy I took it to quoted me for $180 to rebuild the whole thing, including a brand new Bosch voltage regulator. Full story here: http://www.brickboard.com/AWD/index.htm?id=1344154&show_all=1

    I don't know what the lifespan on the knock sensors is. I recently did the PCV job and passed right over the knock sensors. My car's not as old as yours, but it has more miles.

    It would be a good time to install those o-ring seal kits on your injectors.
    These are the parts for my car: http://www.fcpgroton.com/category-exec/category_id/156/nm/Fuel_Injectors_and_Parts/sub_top_menu_item/by_make-by_model-by_year/by_make/78/by_model/1464/by_year/48

    It would also be a great time to clean your throttle body all out with a nylon brush and replace the throttle body gasket.

    It's a great time to change that little o-ring at the base of the oil dipstick, since unbolting it from the intake essentially unbolts it completely, it will just pop right out.

    It's also a great time to replace all the vacuum lines that run along the driver's side of the head/block with the PCV hoses. There's a bunch of them in there of various sizes, and it takes a bit of work to pull them out and replace them one by one (do it one-by-one so you don't put them back in the wrong order/arrangement) but it's well worth it.

    Pull your idle air control valve off and clean that out good too.

    I guess that's all the suggestions I have for you!

    I found it much easier to do the work after I took the battery and the breather box out. FYI.







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      PCV Job and Alternator 850

      posted by  someone claiming to be Margaret on  Mon May 4 14:44 CST 2009 [RELATED]

      We have to drive about 600 miles this weekend for mothers day. Would you advise against it? Also, my husband took one of the covers off the "tree" by the throttle body and this seemed to relieve some of the internal pressure. Please share your thoughts, don't want to blow the thing up on the way to my mother in laws!!!!

      Margaret







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        PCV Job and Alternator 850

        posted by  KlausC on  Mon May 4 17:12 CST 2009
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        last visit: Fri Oct 24 10:15 CST 2014
        [RELATED]

        Put that little cover back on the Tree! It is better to unplug the PCV hose that comes from the oil separator and just let the crankcase breath into the atmosphere.
        So you are not going to do anything before the weekend. Pull the PVC and clean it out, throw away the screen. Then go on your trip.
        --
        My name is Klaus and I am a V ♂ lv ♂ holic.








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          PCV Job and Alternator 850

          posted by  someone claiming to be Margaret on  Mon May 4 18:06 CST 2009 [RELATED]

          Hi Klaus,

          Is that the large hose the tree is connected to? Sorry, I'm a bit confused.

          Margaret








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            PCV Job and Alternator 850

            posted by  KlausC on  Tue May 5 03:58 CST 2009
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            last visit: Fri Oct 24 10:15 CST 2014
            [RELATED]

            Nothing should ever be disconnected or left open on the vacuum tree, that lets unmetered air into the intake and messes up the computer making the engine run too rich.

            The PCV on your car is between the throttle body and the air cleaner, there is a hose that comes up from the oil separator box (about 1/2 inch dia.). Disconnect that hose and cover the hole that is left in the PCV.

            --
            My name is Klaus and I am a V ♂ lv ♂ holic.








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              PCV Job and Alternator 850

              posted by  Ken Temkin on  Wed May 6 09:19 CST 2009
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              last visit: Wed Oct 22 12:06 CST 2014
              [RELATED]

              Margaret,

              I would take a much more conservative approach to taking this car on a 600-mile trip in the condition it is in.

              To be brutally honest, if you are "confused" about what you are disconnecting under the hood, then I would not be disconnecting anything, no less driving 600 miles with something disconnected that you don't appear to know what it does.

              Those lines going to the vacuum tree on the intake manifold expose your engine to unmetered air. Introducing unmetered air, under certain circumstances, makes various cylinders of your engine run lean, and under other circumstances, makes various cylinders of your engine run rich.

              Either way, on a 600 mile trip, you risk damaging your engine.

              An extended-trip lean mixture and you will burn valves, or worse. An extended-trip rich mixture you will damage your rings, pistons and cylinder walls.

              Just because disconnecting some lines appears to make your car run better around town, does not mean that it is good for you engine under the extended load and mileage of highway driving.

              So, unless you really know what you are disconnecting, fix the problem (oil separator and all new PCV lines), then go on the trip.

              Or rent a car for the trip.

              Ken








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                PCV Job and Alternator 850

                posted by  unggthat on  Fri May 8 06:26 CST 2009
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                last visit: Thu Mar 6 10:37 CST 2014
                [RELATED]

                As correct as you are on potential engine damage, I think you may be a bit too negative here. I've known people (surely not myself...) to run cars with gaping holes in the intake piping for thousands of miles before realizing it, then running the engine for another 150,000 miles before the car rotted away. Is there potential for engine damage? Yes. Should you run with a hole in the vacuum tree? No. But will the car be alright? Most likely, yes.

                If it were me and I had to take the trip, I'd undo the breather system so it vents to atmosphere and plug the hole on the intake. Then it'll be better than nothing.

                I do second the point that if you don't know what the various parts are in the engine, you should be VERY careful when replacing the PCV system. There is a lot you could mess up there. Make sure you have a manual that covers the procedure, at the very least.

                Nate

                --
                1997 850, 1979 242GT, 1990 740GL







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