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ok, guese you all know my 940t..uses huge quantities of oil, doesnt leak it burns the stuff - but no great clouds of smoke...anyway...
i recently scored a spare inlet manafold (inc injectors, fpr etc) from ebay and although the outside was filthy the inside was very clean....
I was struck by the thought that mines clean on the outside but filthy on the inside...
now i have a theory that the oil usage is down to valve seals...(compresion good etc) and haveing read some stuff on here about 'sea foam' which we dont get in the UK thought i would try a similar trick with redex (similar stuff fuel system cleaner etc) ...now being a cautious so an so and not wanting to risk hydrolocking the engine i decided to stick 50ml in via the vacume line to the manafold (using a small funnel so i could put it in over about 2 minutes in a very slow trickle...at idle)
after this i let it sit for 30 minutes (they recomend this if you squirt it direct into the cylinders) to soften the crap...
started it up and had an instuntanius and solid miss on one cylinder....took it for a run thinking the crap might blow out...nope...
so i took the plugs out - being carefull to know which plug from which cylinder...- now the plugs hade been in about 4-5k miles and have been there thru heavy oil use, auto rx etc...the results are as follows...
cylinder no 1 (fan end of engine) - heavily fouled, wet. oil nasty
cylinder no 2 - fouled, not wet, better than 1
cylinder no 3 - fouled, not wet, better than 2
cylinder no 4 - ok (ish) looked like its been runnign a tad rich...
after cleanign the plugs went back in and she runs sweat as a nut...even sorted out a bitt of a rumbling idle...
the majority of the fouling came off with methalated spriit, a tooth brush and paper towel - although some of it looked quite burnt on suggesting the conditions had ewxisted for some time but the redex had just shifted a load of loose crap and made it worse...
now my question is...what would produce this heavy foulfing on cylinder no1 geting better towards cylinder no 4..., I am thinking cross talk from inlet valves via the manaofld with say no1 leaking like a bitch....but could it be to do with oil prusure diferences in the head etc...??? any thoughts?
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A turbo can be the source of oil usage. Our '90 uses about 1/2 quart every 1000 miles, but it does not foul plugs and it passes emissions testing.
How much oil does your brick use per 1000 miles?
Did you have fouled plugs before you ran the redex in?
If you do not have clouds of oil smoke, I suggest a new set of plugs, inspect and clean your spark plug wires (I use WD 40 and a rag), and route the wires carefully to avoid shorting and cross fire.
If the plugs aren't fouled in 1000 miles, it isn't be all that bad.
Get some extra plugs and a spark plug cleaner, schedule frequent plug changes.
I had a '66 Dodge with a slant 6 (kinda like the Volvo engine) that needed new plugs every 2 weeks! I drove it for two years like that and had few problems - I had 18 extra plugs and cleaned them at work in batches!
BTW - I read somewhere that the #1 cylinder in this engine is usually the one that goes first - I do not remember why though.
--
'96 855R, '95 855, 854, '90 744 TI, 366,000 miles put on 7 bricks
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new turbo on car 5k ago...(to try and solve oil usage!)
depending on use car uses 2-10ltrs oil per 1000 miles, worse on long high speed trips
plugs not misfiring prior to redex...other than that dunno!
no oil smoke whatsoever (and no oil leaks either!)
plug wires 2k old or so, so is the distributor cap & rotor arm, leads as per volvo manual on routing ...
fun isnt it!
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Hi james,
I believe the #1 cylinder is the 1st to fail in early K blocks (with the 9mm rods) when they recieve too much boost...
--
Chris. Halifax N.S. '91 745Ti, 291K km and '91 745 NA, 386K km.
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There are 4 ways for oil to get into your cylinders.
1) Blown turbo seals - ruled out by plug indications, all plugs would be equally fouled if it was this.
2) Bad/frozen rings - have you run a leak-down test? It will isolate any cylinder leaks including rings, valve seats and...
3) Blown head gasket - see #2, have you tried the tissue paper trick on the oil filler? With the engine running, place some semi porous paper over the hole (hold onto it). There should be a slight vacuum indicated by the paper being drawn into the hole. If it bulges under pressure it indicates an abundance of blowby gasses which could be a clogged PCV system and/or some of the leaks associated with #2.
4) Leaky valve seals - Eliminated all of the above? This is what is left.
Your plugs indicate a single cylinder problem, I seem to remember reading someplace that cyl #4 plugs will indicate leaner/hotter combustion under certain conditions, you may want to run a search for that. I suspect you may be right about the valve seals on #1. Don't read too much into the fouled state of #2 & #3 condidering the auto Rx and redex treatments. If you are reusing your plugs, why not swap #1 & #4 and see if the deposits burn off in #4 and appear on #1? Just a thought.
--
Bob Kraushaar '94 945T, '88 240, '84 242Ti, '88 300 TE, '89 560 SL, '68 Shelby GT-500 KR
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hi bob...sage advice as per normal...
havent done a leak down test...have doena static compression test (which was ok)
at idle there is vacume on the filler hole (palm of hand over it test!), more revs at idle = more vacume...
have dropped new plugs into it yesterday....figured for £10 givene they have been there for 3 years what the hell!
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From what you have stated, it sounds like a valve seal to me. Pop the cover and poke around the seals to see if they are all in one piece, or not, or hard & brittle. Worse case scenario has the head coming off and the guide getting knurled or sleeved but try new seals first, you should be able to R&R them w/o removing the head. Never done it myself though on a Brick so I can't say for sure how easy/difficult it is. Easy/breezy on a Ford small block;-)
--
Bob Kraushaar '94 945T, '88 240, '84 242Ti, '94 F-150, '88 300 TE, '89 560 SL, '68 Shelby GT-500 KR
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steve says hes done it...thinking it may be a good time to pull the head and have a look at the seals, bores, valves do PM change on the head gasket...(and a decoke)
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