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Old 11-23-2004, 09:28 PM   #1
greenhorn male
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Question Engine smokes (blue) badly at start-up...

...then not noticeable after warm-up. On very cold days start-up smoke is hardly noticeable. A few people suggested I have worn valve stem seals. It is a 1987 with a 305 TBI with just over 80k miles. Someone said with an air compressor it is an easy job without removing the heads and that they sell kits with everything needed but the compressor to complete the job. Has anyone done this before? How easy was it and were you happy with the results. If you had to do it again would you do it the same way or pull the heads?
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Old 11-23-2004, 09:43 PM   #2
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Definitly sounds like valve stem seals, I'd just do the job with the heads on the engine already, also helps you to make sure that none of your valves are burnt and leaking
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Old 11-23-2004, 10:00 PM   #3
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Quote:
Originally Posted by Russell
Definitly sounds like valve stem seals, I'd just do the job with the heads on the engine already, also helps you to make sure that none of your valves are burnt and leaking
Russel...could you give me more details on how it is done with heads on?
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Old 11-23-2004, 10:04 PM   #4
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I haven't done it myself, but I do know you need to buy a fitting that attaches to your air compressor, and screws into the spark plug hole, you then pressurize the cylinder so the valves will not fall in. You then take the rockers off, the springs off, and after that, I'm not sure, never actually done the job yet.
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Old 11-23-2004, 10:12 PM   #5
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Ok, thanks anyway. I called 2 shops and the price they quoted included head removal and I was afraid I might end up with leaks I didn't have before.
Maybe someone else who's done this will chime in with some details.
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Old 11-23-2004, 11:12 PM   #6
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Its going to be a peice of cake on a truck, I put new valve springs on a 350 that was stuffed under the hood of a 87 Z28.

All you gotta do is bring that piston to TDC (top dead center) and either fill the chamber with a small rope/cord, or get the fitting you need to screw into the spark plug hole and hook your compressor up. I have a snap on compression testing kit and removed the shrader valve on the part that screws into the head and then the other end where the guage attaches uses the same fitting as my air compressor.
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Old 11-23-2004, 11:42 PM   #7
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Shouldnt be to difficult, you just wanna make sure you dont drop a valve(thats what the rope is for)
1. Stick some rope in the hole
2. bring it up to TDC,
3. Compress the spring
4. take the retainer off
5.take the spring off
6.slide the old seal off and thenSlide the new one one
7. Re install the spring and retainer
8. lower the piston
9. take the rope out
10. move to the next one
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Old 11-24-2004, 01:03 AM   #8
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11. Adjust the valve lash at each rocker arm when finished installing all the valve seals.
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Old 11-24-2004, 02:44 AM   #9
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Thumbs up Thanks for all the advise.

Is the rope preferred over the compressor? If rope is used is there a preferred type and diameter rope? If I use my compressor, how much pressure do I pump into the cylinder? Thanks again.
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Old 11-24-2004, 07:14 PM   #10
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ohh yeah i forgot the most improtant one!
Id prefer rope so that there no chance of loosing pressure and dropping a valve but its up to yourself.
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Old 11-24-2004, 07:52 PM   #11
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How much pressure? I would say about 75 psi will work fine just to be on the safer side. So that if it does bleed down you will have time to turn it back on. But I dont think you would have a problem with it bleeding down, given that the air compressor is good. As long as all the fittings are tight and dont leak air it should hold the valve plenty long enough to change the valve seal and assemble everything back together. You could also hook it up and just see how long it takes to bleed down if at all. One of those small magnetic sticks are nice to get the keepers out while compressing the valve spring. Keep all the rocker arm assemblies separate and labeled so that they go back where they came from.
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