BG 109 EPR for stuck rings

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Nov 17, 2010
Hello all, Just bought a can of BG 109 Engine Performance Restorer and am planning to do a flush with it next weekend. The aim is to free up stuck rings in the hope of curing oil consumption. This is after I have tried cleaning up with an HDEO for some 10K Km with no apparent results. I elected 109 as ARX or MMO are not available here. My engine is an Alfa Romeo 2.0 CF3 Twin spark which has low tension 2 mm oil control rings with no drain holes. A common fix to the consumption issue (up to 1 Ltr per 1,000 Km) it to replace these with 2.5 mm rings from the previous model and/or drill 2 or 4 holes. Aside from this, the engine specs 10W40 Semi for normal use and 10W60 for spirited driving. My PCV is fine. The engine runs sweet and vroomy as ever with some 150K. Nice smokescreen on WOT (Cat is knackered and barely passed annual MOT with a high CO reading). My plan is as follows: 1. Warm up, dump the can into the engine and idle for 15-20 min. No fast idle. 2. Shut off, drain (including tilting for max drainage) and replace oil and filter using some cheap oil. 3. Run for an hour or so, not over 3,000 RPM and just a bit of load. 4. Shut off, drain and replace oil and filter (Valvoline HDEO 15W40). 5. Run for a month (~2.5K Km). 6. Monitor Consumption daily. 7. Replace again - with regular 10W40 Semi (ENI Agip). Is this a careful and conservative approach? And some additional questions: 1. Do I still need to fear solvent leftovers after a second replacement? 2. Do I need to run more than an hour with the cheap oil to get all leftovers out? 3. Can I go bolder and run for 30 minutes with the 109 in (as recommended by the rep.) or am I risking my big ends? 4. Already have MoS2 in right now, should I fortify with MOA for extra Zinc? Promise to post the results once I do. No provisioning for UOA labs, sorry. Thanks, Tuval
I have never used this particular product, but I am familiar with other BG products (brake services/fluid, transmission services/fluid.) I would say the best course of action is to contact BG customer service and they will direct you from there. They have outstanding customer support, and stand behind all of their products. Good luck!
Originally Posted By: 01_celica_gt
No oil return holes, how old is it with that design?
This is a rather old design. FIAT sourced iron block that was somewhat based on the Alfa Twin Cam with Alfa engineered head. Suffers from blow-by, high consumption, soft shells and is sensitive to low oil level that results in Big End failure and/or rods and pistons flying about. The original CF1 & CF2 variants did not suffer from the rings and these were replaced for CF3 by low tension ones with no holes in order to comply somehow with EURO-3 or 4 IIR. The cacophony is pure delight though on WOT... laugh
Originally Posted By: jk_636
I have never used this particular product, but I am familiar with other BG products (brake services/fluid, transmission services/fluid.) I would say the best course of action is to contact BG customer service and they will direct you from there. They have outstanding customer support, and stand behind all of their products. Good luck!
I will mail them. Thanks!
Any remaining solvent should not last very lone once engine gets up to temperature. Have you considered a Piston Soak?
The approach is smartly conservative. Not sure if you want the engine to be hot for this though - you may flash solvents too rapidly, which might defeat tge purpose. But the oil change approach is smart. I would consider removing plugs and adding some via the plug holes. Turn the engine over by hand and let it sit a while.
Same here. I would start the flush on a cold engine to prolong the exposure to solvents. I would also skip the cheap oil step and just keep next OCI a bit shorter. With no oil drain holes, you probably need to do engine flush every oil change. I would also use 15W40 HDEO/diesel oil all the time, use conservative OCI, and skip the 10W40 junk. No need to start with inferior oils and pile additives in it.
Thanks Expat, JHZR2 and Jacek for your advice! 1. I will execute from cold. 2. I always think about doing a soak from the holes, but for the sake of isolation, I will try it (with a scope) after analyzing the results of the straightforward approach. 3. I must say I prefer an HDEO just on basis of theory alone even if I didn't get the results I wanted. It might be due to the fact that I was not able to source Valvoline All Fleet till now. If this proves to be a reliable source I will likely stick with it. Jacek - I completely get your point bout inferior oils. 4. I suppose that success can be measured as anything that will reduce the consumption by some noticeable percentage (above 15 or 20%). If so, it will likely be very wise to do short OCI's and a flush every time for at least 3 to 5 times and see if it improves. Am excited and scared I can't wait to do it already...
Update: I have done the first phase: 1. From cold, heart pounding, dumped the can into the engine and idle for 20 min. No fast idle. Noticed the nice play by BG including a seal in the can, showing that it is unharmed by the flush juices. During this step, I heard the hydraulic lifters ticking more and more as the minutes progressed. This unnerved me slightly but I kept on. 2. Shut off, drain (including tilting for max drainage) and replace oil and filter using some cheap oil. Replaced with 10W40 ENI Agip Semi that comes fortified with some Ester. The old oil stank from the EPR, but I must say was not very watery. Seemed just like normal viscosity as previous changes. Was regularly very black so no real reference here. I think tomorrow I will stick a stick in the old oil and see if anything settled down as result of EPR breaking down the chemistry. Was not able yet today to drive too much. Only some 20 minutes. oil is still fresh but is stained. I think I have to replace it anyways tomorrow after some more moderate driving. I want to be sure no gunk or solvent gets left behind and that I have the peace of mind of a strong detergent of the Valvoline All-Fleet and a new filter. More updates tomorrow end of day - and of course after I drive it to work Sunday.
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Update: Took her on a short 30 min trip, driving moderately. Then proceeded to change oil and filter. Although the dipstick showed somewhat still clear and golden with a light stain, the oil that came out was very dark (not pitch black as before or as usual) and still stank of EPR when shoving my nose at it and giving it a good snif. Replaced filter and poured in Valvoline all fleet plus 15w40. Gave it a run and now all seems well. Colour is very light now and the look under the oil filler cap is very clear, unlike before where you could always see dark puddles here and there. Obviously to do with the double change and regardless of the flush. Engine note seems a tad smoother and the engine braking seems sharper and more pronounced but it is probably my wishful positive thinking... Will update after tomorrow round trip to work of 120 Km and every day to monitor behavior and oil consumption.
Update: 2nd day of commuting to work. 35 Miles each way. Point of inspection is after 3 legs or 105 Miles. Oil is clear but darkening with noticeable stain on the blot test. Down 100 mililiters so around same consumption as before. Maybe less by a bit. Engine feels and sounds much smoother and I feel as if it begs for flooring it. Could not stop myself and I think the acceleration feels improved. Especially mid range. While first three legs I took it rather moderate and not going over 5K, then this evening on the 4th leg I could not resist and took her beyond 5K. Will check in the morning what this last trip cost in ml, after the oil settles during the night.
And one more update: Now after 7 legs or ~245 Miles, I can say the consumption seems below normal. This is with quite a bit of spirited driving when there are no traffic jams. Till now, I have only topped up once as previous post - 100 ml. I will update again only weekend or next week, according to progress and if I have another top-up required.
I've used BG109 a few times in the sled and it's worked very well. However, the instructions say to pour it into an engine at operating temperture, not cold. Remember, hot solvents work better than cold ones. As the sled has a turbo, I also drained the oil cooler. My hot syn. oil + 109 came out like water as the 109 reduces the oil viscoisity to nearly zero. Sounds like you've had a positive experience with it! Thanks for posting updates reflecting your experience. Far too many here just drop off, leaving the rest of us to wonder how it turned out!
1 week following the flush and some 400 ml down after ~350 Miles. This is a notable improvement - around half the consumption. I will continue to monitor and gather more measurement points to report on. If this still works out in lowering consumption, then it is a major breakthrough for me and for the community. I already am thinking that I should be repeating this cycle in a month or so. I reckon the ring area will benefit some more. During this month I plan to replace the inlet manifold gasket and check the phase variator solenoid for leaks. These are two usual suspects for this engine aside from ring issues.
Bad news folks. Big end damage to my beloved Bella. Thought I was in 5th and decided to overtake. Two clicks and I realize I was in 4th and now in 2nd as the revs shoot up. Moments later a tick becomes a knock and my worst nightmare pounds me in the face. The death rattle is here. This is an old enemy of mine. Last time we met was 3 years, 11 Months and exactly 100,000 Km ago. Aside from my heartbreak, I am now checking my options. Either shells possibly with crank regrind or scrap. Cannot afford a full rebuild. Thinking of doing this myself. Shells first and if they go again, then maybe my wife will be happy as she is not really fond of her. I don't think this is the result of the flush. Twin Sparks are known for butter shells and a death rattle is the number two cause of death for them right after belt snap. However, it might be a combination of the excessive stress coupled with some debris clogging or what. Guess I should have stayed on the more cautionary and conservative side when looking for cures.
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Bummer! Very sorry to read! Good luck and best wishes with whatever you decide to do. "Rich folk spend money to save time. Poor folk spend time to save money."
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