| Author | Message | ||
     Miguel A. Garcia Prolific User Username: magarcia Post Number: 116 Registered: 3-2005 |
Hello. Last week I added to engine oil of SRH3430 an additive called Slick50. Just few minutes after and with only few kilometers runned (2 or 3 Km) the engine started to make a noise as a "SHHHHHHHHHH" in the low left side. Is the most close to a blowing noise or air scaping noise. This is the best examples that i can find to compare the noise. This noise is louder when more gas is aplied and is not noticeable whil idle running. Also car looks have less power. I have not runned more and this week i will change oil and filter, but do you have any idea of whats this? Could be the oil filter clogged by the small teflon particles of Slick50 and this noise is some of the compression valve? sorry, but i am confused. | ||
| Richard Treacy Grand Master Username: richard_treacy Post Number: 1036 Registered: 4-2003 |
Name withheld, see ******* instead. I assume it is the stuff advertising that 'with all types of motor oil, (it) is safe for all automotive gasoline engines and will not void manufacturers' warranties.'. That's only if the manufacturers don't find out. I guarantee that you will never find any motor manufacturer which condones this treacle stuff. It is pretty popular in shonky used car yards, though, as it helps to shift otherwise smoky and leaky cars to struggle on for a few more months, and expecially the <*******> syrup for terminal wrecks (they seem to think that a paltry 50,000 miles is a high mileage, but that's just a sales ploy as any car, Holden or BMW alike, runs like new at 160,000 miles these days on modern lubricants), claiming that it 'includes a 50,000 mile engine limited warranty', in other words nothing. Opel and Mitsubishi alone give you a 50,000 mile (80,000 km) full service warranty these days. That's nothing, as some cars come with 100,000km warranties. Even that little Smart has a 10 year warranty now. Forget this stuff. Save the silly cost of additives and go for the real thing, like a fully-synthetic 0W40 or 5W50 as endorsed by Crewe if you want the best. If you want to clog up your hydraulic tappets and piston rings for a start, ******* is for you. | ||
| Miguel A. Garcia Prolific User Username: magarcia Post Number: 117 Registered: 3-2005 |
hello, oil and filter replaced. Filter not clogged but the oil much thicker than acceptable with only 3000 miles. Never more will use this kind of aditives. I use to use common mineral SAE W20-50 from a local reputated brand (REPSOL) The SHHHH noise was a little hole in the first exhaust element. Just coincidence i think. Thank you | ||
| bob uk Unregistered guest Posted From: 80.3.64.11 |
Sounds like and exhaust blow are all the cyliner firing easy to lose a cylinder on a V8 and the engine will still be reasonably smooth but down on power. slick 50 does indeed contain telflon particals all of which are bigger than the the oil filter fitration size which is measured in mircons ( millionth of a metre ) So when the engine is started they all get collected by the oil filter to stop them getting to the engine brgs. which is what the filter is there for Most engine oil additives are made by using 99%140 grade oil ( it has to be thick because the customer thinks that the thicker the oil the better it will be ) and 1% magic ingrediant which is the case of slick 50 is telflon bits. Telfon is used to make frying pans non stick and bushes and bearings that are lightly loaded or where a bit of give is needed. Du-Pont have not approved telfon for use in engines and in fact Du_pont refused to supply direct a certain manufacturer teflon due to misuse of a Du-Pont product. Further I remember a court case with Du-Pont as the complainant The 140 oil would have mixed safely with the engine oil and if you had 20/50 you now have 20.5/50.5 grade. Slick 50 does nothing. It neithers damgages or enhances No oil company , no goverment agency. no car maker any where in the world approve of oil additives and in most cases the reverse is true. There are some additives that are usful such as molyslip in hypoid axles --- but good quality oil already have this additive so I wouldn't interfere with the oil company's formulation Note if an oil filter gets totally blocked the by pass valve will lift and save the engine from oil starvation. Some engine do not filter all the engine oil at once some oil is diverted to the oil filter and some to the engine brgs. This does not mean that you need not change the oil filter because a blocked oil filter will lower the oil pressure to the engine bearings allow unfiltered oil into the bearings. I have in the past been sucked in by a persausive bit of clever marketing. Now I have got old and wise and ugly and I tends to heap scorn upon marketing of such products. Best one I heard was when the lead was taken out ot petrol. Some guy tried to convince my boss that putting slugs of tin in the fuel pipe would replace the lead. My boss being even uglier than me said never on your life does petrol dissolve tin other wise solder on petrol tanks would not work would it. The salesman had no counter attack -shot down no survivors. (Message approved by david_gore) | ||
| David Gore Moderator Username: david_gore Post Number: 610 Registered: 4-2003 |
Hi Bob, The tin replacement scam also did the rounds here - would have enjoyed being present when your boss's riposte was given. You have summarised the situation completely. | ||
| Miguel A. Garcia Prolific User Username: magarcia Post Number: 119 Registered: 3-2005 |
Hello Bob, about the possibility of a cilinder missfiring, was a reasoble option, as the engine really has a leak of power. The engine at idle speed mantains fine the idle revolutions. It sounds quite fine at idle. If i take off one by one each spark-plug wire, it goes abit down each time i test each cilinder, what in my opinion means that all cilinders are firing right. Anyway, once driving, if i take the pedal lightly and drive too smooth, the car goes fine, but if i push the pedal, or i ask it (the car) to go faster applying gas, it keeps as breaked. The engine takes a lot of time to get revolutions and in highway it takes no more than 90 km/h. At smoth driving in town, no problem. It seems as if hand brake was applied all time!!!, but of course is not that!! any idea? could be a carburettor problem? Air filter has no more than 500 Km, and all this symptoms started at the same time that the blowing noise that i mentioned before. Could be a problem of the convertor involved in the authomatic transmission or any other thing about the transmision? I feel that could be carburettor Thank you | ||
| bob uk Unregistered guest Posted From: 80.3.64.11 |
I have just remembered this one. Fitted to the fuel line is a set of magnest and a coil which is connect to the ignition via a little black box contianing some rubbish circuit. It is meant to polarise the fuel molecules so that the burn better and you get more power and better MPG. Trouble with that is that there is not one piece of scientific evidence that polarising fuel makes it better. Electric fuel pumps have a magnetic field because there is a motor of some sort or a large coil as in SU pumps. I have fitted electric in place of mechanical and never noticed any difference. I always think that if this was true then why is it not fitted to cars by the makers? bearing in mind the amount of money spent in design to make the car use the least amount of fuel possible. (Message approved by david_gore) | ||
| bob uk Unregistered guest Posted From: 80.3.64.11 |
Sounds like the mixture is weak. This causes the engine to feel reluctant to rev. You said you heard a blowing noise. The mixture setting of carbs does not just go out of tune. Check that all the pipes that supply vacuum from the manifold are not leaking. Air leaks will make the mixture weak Mine has 2 -cruise control and auto transmission. If you spray WD 40 at joints and the engine runs better for a moment followeed by a puff of WD smoke from the exhasut then you have found a vacuum leak. There is a fault you can get with a torque converter. The one way clutch on the centre element can fail which makes the torque converter behave like a fluid flywheel and you get no torque multiplication this makes the car feel slugish up until the car gets to say 25 mph ( it varies from autobox to autobox.) This is tested by finding out the stall speed of the converter which is usually about 1800 rpm. Put the car in drive hold the car on the brakes and apply full throttle and note engine rpm. THE FULL THROTTLE MUST ONLY BE APPLIED FOR 10 SECONDS OTHERWISE THE TRANSMISSION COULD OVERHEAT. Engine revs too fast means gearbox is slipping and bands are worn. Engine revs too slow means torque converter is faulty OR THE ENGINE IS DOWN ON POWER. I HaVE ONLY EVER SEEN 2 TORQUE CONVERTERS IN 40 YEARS DO THIS SO ONLY SUSPECT THE TORQUE CONVERTER AS A LAST RESORT. Torque converters are like a gearbox because they mutliply the torque from the engine the maximum is 2:1 which is at low engine revs and when fully locked the ratio goes to 1.1:1. The 1.1 is not 1 because the converter has a bit of slip. Modern cars at about 45 mph have a mechanical lock which locks out the converter to give a true 1:1. Autoboxes don't actually use much extra petrol to run the gear box --it is the torque converter that uses the extra petrol ( which heats up the fluid ). SO a 3 speed auto is actually a 3 variable ratio transmission 6 speed if you like. SAFETY NOTE WHEN WORKING ON CARBS WITH THE ENGINE RUNNING DO REMEMBER THAT IF THE CAR WAS TO BE ACCIDENTLY KNOCKED INTO DRIVE OR REVERSE THE CAR WILL DRIVE OFF AND MAYBE RUN YOU OVER. THIS HAS HAPPENED MANY TIMES IN GARAGES. So chock the drive wheels and or take the autobox cutout module from the fuse board whiler the car is in park then it cannot select any gears when you stall the engine and reach in through the open window to restart the engine and knock the column change . Or take the rear wheels off. The hand brake will not hold the car against the engine running at say 1000rpm and in gear. (Message approved by david_gore) | ||
| David Gore Moderator Username: david_gore Post Number: 614 Registered: 4-2003 |
Hi Miguel, Another possibility is the ignition static timing is not correctly set, the distributor is not advancing the spark correctly as engine speed increases or the points dwell is not correct. You will need access to a timing light and dwell meter to check the static timing and points dwell. Checking the advance curve will require removal of the distributor and finding an auto electrician with a distributor test bench - this will invariably be someone who did his trade in the 1960/1970 era when these were an essential workshop test item. | ||
| Miguel A. Garcia Prolific User Username: magarcia Post Number: 120 Registered: 3-2005 |
Bob, the blow i heard was just very small hole in the exhaust. Once repaired with emergency kit, it rouds quite fine as a little cat. At iddle, in Neutral, engine keeps revolutions fine, if i push gas, its takes revolutions fast and cleanly. The problem is only while driving. If i drive it at the point of the foot (very gently and with very low gas, i hope i do understand myself, sorry) it goes exactly it was expected to do, smoth and fine. But if i push more the fott to give more gas, then it started to go down, and as mor gas i push, more down goes the engine. Is like if the fuel was full in the carburettor, but i am not familiar with this kind od carburerrtors, so i do not know if it would be or not. Could be easily keeped out the cover of each carburretor to be cleaned and refill the oil inside, or it would be needed a most deep cleaning process and tuning up them? Any idea? With these details about the symptoms, what do you feel about it? Thank you all again! | ||
| Miguel A. Garcia Prolific User Username: magarcia Post Number: 121 Registered: 3-2005 |
Hi again, i just have fall in what could be the cause of this. While moving tins in the garage, i saw that the oil wich i used to add to the dampers in both carbs was SAE 80W-90 !!! Stupid of my!!! I am sure that this is so much thick that is the cause of the failing of the carbs because some wrong in the suction chamber!!! Could be this the cause? How do i take out this oil?? is it necessari to simount the cahmbers and clean them, and piston inside?? Thank you again!!! | ||
| Miguel A. Garcia Prolific User Username: magarcia Post Number: 122 Registered: 3-2005 |
Well, yesterday i dissasembled the suction piston and suction chamber of both carburetters and cleaned them in petrol. In both carbs, the piston and the interior of the chamber had traces of some like carbon deposit, wich i cleaned smothly. The neddles were not dismounted nor touched. the springs were carbon black too. I cleaned them also in petrol. After i reasemble them in the reverse way, and refilled the oil in the dampers. Switch on the engine and the road test... at very low speed, all ok, but when i ask the engine with more gas to go faster.. OHHH; the same: FLOODS. I am yet cinvinced that overflowing fuel bowls are the responsable if this problem. What do you think? is an easy task to do by a non experienced DIY? Any idea? The main problem also it that official Bentley service workshop in Madrid will not receive the car till next month as they are full of work and also if the need them any spare to replace, all spare suppliers will ve closed for hollydays. All other carb workshops wher i have asked, do not want to touch the car. This is the problem that i have spoke about here before. In Spain, most brithis cars are like the black beast for most mechanics, bu i do not not why, because here we had many brithis cars in the 60īs, 70īs and early 80īs (triunmph, morris, austin, mini, etc...)but i cannot find anyone who can afford these cars with a reasonable trust in his work and an affordable, or at least a reasonable price. | ||
| Patrick Lockyer. Grand Master Username: pat_lockyer Post Number: 591 Registered: 9-2004 |
Miguel i feel like this is a Goose chase on reading the posts! Fist go to any local mot garage in Spain and get your emissions checked.I would like to know your stable and average CO and HC readings first. This will confirm many things before this guessing game will extinguish its self to an unsatisfactory end. | ||
| bob uk Unregistered guest Posted From: 80.3.64.11 |
If the carbs are flooding then petrol will come out of the overflow pipes which must be fitted for safety sake otherwise petrol will lie in the valley of the engine awaiting a stray spark. The overflow pipes ( black in colour about 1/4 inch bore) go to the bottom of the engine each side. If they are flooding then change the needle and seats in the float bowls. and check the floats for punctures. If they have petrol inside them then they are no good. These parts are common to other makes that use SU carbs and are available from Burlen Services. I would do as Pat Lockyer says and take the car for an emission test, or get a mobile tuner to have a look because the problem is usually very simple if they car was running OK. In my experience putting thick oil in the dampers will not cause the problem you have. The thick oil will slow down the piston movement but not that much and the piston will catch up very soon. If is differcult to find whats wrong with out actually being there. I have never understood why mechanics are shy of SU carbs because they are in fact such simple instruments. (Message approved by david_gore) | ||
| Miguel A. Garcia Prolific User Username: magarcia Post Number: 123 Registered: 3-2005 |
Hello again. Problem solved!! but it was a different cause i could not suspect...I will explain all the process. As sugested by Bob and Patrick, CO levels were very high: 12%, so it was needed a carb and timing tunning. I carried SRH3430 to an specialist in classic cars (I could see at their garage some other vintage cars as Hispano-Suiza, Pegaso, Aston martin...). He told me that was needed a carb and timing checking and tunning. As i had a Pertronics ignition bought from some months ago, was the time to change it too. So they cleaned the carbs, new fuel filter, air filter, checked sparkplugs wires, ignition coil, changed spark plugs and changed the contacts for the new pertronics. Tuned the carbs, CO level in 2,8%, but when road testing was done, ohhh no!!: the same problem!!! The mechanic looked to the firts exhaust expander and VOILA!! was colapsed inside!! that was the firts symptom was this SHHHH noise!! the exhaust gas broked a little hole because the over pressure of the gas. The all inside fibers (I saw it, a kind of steel wool, was colapsed all in the rear hole closing the outgoing way and that was why it did that failing just whe i push gas while driving!!. Well, now i have the car yet well tunned, with CO at right levels for Spanish MOT again, cleaned carbs, and an empty firts exhaust expander, which was opened to take awy the residual closing deposits, and reclosed and sealed , just waiting to receive a new spare to replace it. Another time, not all was so evident as could be suposed.. Thank you again to all you for your support. regards, Miguel | ||
| bob uk Unregistered guest Posted From: brig-cache-4.server.ntli.net |
The mechanic down well to spot a collasped exhaust -explains every thing. The engine was down on power because the gases couldn't escape so the fresh intake couldn't get in. Bit like only having 1/2 throttle available. I have seen this before especially on 2 stokes due to excessive carbon build up in the exhaust ports. The syptoms are similar engines starts and idles nice but just will not rev and when trying to drive it ( usually a motorbike ) the engine bogs down. Fist time I cleaned a 2 stoke exhaust system out I was amazed at how much better the bike felt ( Suzuki 100cc 1970's ) (Message approved by david_gore) |
