Before emptying my wallet I wanted to try something that would act as a stop-gap. BlueDevil Rear Main Sealer is a specially formulated additive that you add directly to your engine oil. When this rear seal leaks either the engine or the transmission has to be removed to gain access. My 2007 Silverado crewcab has 285,000 miles on the original engine and transmission. The BlueDevil Oil Stop Leak is a universal application, and will treat leaking oil pan gaskets, valve cover seals, rear main seals, etc. Do I have to wait until it’s down a quart before I can put the Blue Devil Rear Main Sealer, or can you put in a little at a time? There are sleeve kits that can be installed on the crankshaft to restore the surface. BlueDevil products do not sue any petroleum distillates to recondition seals so our product creates a permanent seal. Your email address will not be published. This would mean that the engine needs to be replaced. If you are low on oil, add the product and top it off with oil to get it to the proper level. Thank you for asking about your GMC Sierra. Their cork composite seemed to be the best. The BlueDevil Rear Main Sealer would only be intended for the rubber seals. Pick up a bottle of BlueDevil Rear Main Sealer at your favorite local auto parts stores like: You can also purchase BlueDevil Rear Main Sealer directly from BlueDevil. Lucas Oil Rear Main … If selling the vehicle or paying for a repair is the absolute last thing you … It would not have any effect on rope, cork or any other type of material that may have been used. Then, I heard about Blue Devils Rear Main Seal Stop Leak. The lip that rides on the crankshaft will become stiff and will not be able to seal itself against the crankshaft. I have a 2003 GMC Sierra with 240,000 miles. The rear main seal leak issue is usually caused by a few issues. About a month ago I noticed a very small oil leak… 2 drops smaller than golf balls but larger than quarters… after the truck sat in the garage over night. Your email address will not be published. Where is the rear main seal at on a 1982 f250 auto with a 400 and do you have to remove the tryanny or the motor or both? Solving why the seal failed in the first place is critical to preventing a labor-intensive comeback. Thank you for asking about your Honda Odyssey. I just had my oil changed. The pressure inside the crankcase will push the lip onto the shaft. Best Budget. Seal types There are three types of rear main crankshaft seals in use today; each offers its own features and benefits, along with concerns. GraphTite™ rope seals are miles ahead of any other rope seal out there. Need advice on a dealing with a blown head gasket? Topping off the levels is often more costly in the long run than repairing the leaking gasket or component. On most modern engines, the seal’s failure is due to a condition inside the engine or a component connected to the back of the engine. After two weeks the leak stopped and the Toyota is doing fine. See more from Underhood Service. I have a 2005 Dodge magnum that my son drove once and overheated it and ever since I cannot get it to start and stay on and at first I would fill the radiator reservoir and it was draining and then milky chocolate looking oil started spilling out on the ground I later discovered the old from the dip stick was also milk chocolate colored so I drained it and replaced it and it still won’t start it was leaking from the rear of the engine is this the rear main seal and would ur sealer work for this possibly. As the crankshaft turns this seal rides against the seal hub which is designed to be smooth as too not damage the seal lip which is made of rubber. The main reason for the cost is usually labour, as the transmission needs to be removed from the vehicle to allow access to the rear main seal. Too much pressure will eventually cause the lip to balloon and allow oil to pass. If the seal is installed with a coating of oil, it will start to leak in a few miles. Hi, I have 2004 Honda Odyssey. You can check the oil level on the dipstick. The rear seal fits snuggly around the rear of the crankshaft and keeps the engine oil from escaping. Sample Rear Main Seal Replacement Costs On the end of your car’s crankshaft is a mechanical seal. Adding dye to the oil can help reveal where the oil is coming from. After driving the vehicle for longer periods it doesn’t seem to leak, but on short trips it still drips a little on the exhaust manifold (I can smell it) and leaves about a dime size spot overnight on the driveway. This seal ensures that engine oil does not leak out. . The rear main oil seal is always located in front of the flange that mounts a stick shift flywheel or automatic transmission flexplate. Discussion Starter • #1 • Nov 20, 2016. Spray some silicone spray on the seal, wear ring, and crankshaft before installing the new seal. I have a leak on my rear main seal in my hyundai tucson, where do you check the oil level? I’m at the shop now and they found a cam seal leak. Well, we've got the answers! Our tech department has responded direct via email. Feel free to contact us at 888-863-0426 with any other questions. The condition of the surfaces that the rear main seal rides on is critical. there is a possibility I might have a slow leak in my rear main seal. The rear main seal exists in the back of the engine, around the crankshaft. My rear main seal went out in August 2014 and with almost 200,000 miles, I couldn’t find a mechanic willing to replace my rear main seal. The crankshaft (the internal engine part that the pistons are connected to) sticks out of the rear of the engine, and the flywheel & transmission bolt to this crankshaft. Advising a customer about the potential damage that can occur if they decline a leak repair is not a scare tactic, it is important that they know…. Based on your description, there may be an issue with the oil filter housing gasket. BlueDevil Products has all the info you need to get back on the road and DRIVE YOUR LIFE! My question is would it do any good or better to use “two” bottles possibly to correct the problem? Have you had any experiences with this application? Thanks for your question. and it seals!! Here at BlueDevil we’re hoping to change that myth. You can also send an email to our pro for direct assistance! Average Rear Main Seal Repair Cost – To Have A Mechanic Replace Rear Main Seal The average cost to repair a leaky rear main seal, is anywhere from $800 – $1,200 dollars. No, you would not have to wait until the oil was down before adding the BlueDevil Rear Main Sealer. Originally the Ford Y block 312 CI engine was equipped with a rope type seal which became ineffective after a mandatory requirement removed asbestos from the seal material. … The inside of the rear main seal creates a seal on the crankshaft where it exits your engine to connect to the transmission. These seals have a polytetrafluoroethylene (PTFE) coating on the lip seal that needs to be dry and seat to a dry surface on the crankshaft. “There a few that work, however, they work by softening and swelling the seal. What are the symptoms related to a bad rear main seal? Pictures courtesy of: www.lowridermagazine.com and www.precisionenginetech.com. Because of its location in the engine, replacing a rear main seal includes at least removing the transmission from your vehicle, if not completely removing the engine as well. BlueDevil Oil Stop Leak is more concentrated and is the universal application that will work for various leaks such as oil pan leaks, rear main leaks, valve cover gasket leaks, etc. The seal conditions are depleted over time along with buffers in the oil. Make sure you check the input shaft on a manual transmission for play. any pointers I might be missing? The rear main seal in your vehicle is at the back of the engine and seals the crankshaft as it exits the engine. The reason it is such a costly repair is that replacing it often involves dismantling the transmission and even part of, or all of, the engine. Is the rear main seal covered under Powertrain ? Having a problem with the rear main seal in your vehicle can be a scary thing, mostly because many of us don’t entirely know what that seal is or does. However, after 3 weeks and 800 miles with no apparent leaks, the oil drops have reappeared, the same as before. Its primary purpose is to keep oil sealed inside the back of the engine, which is where the crankshaft and the transmission meet. The rear main seal covers the end of the crankshaft to keep the oil inside the engine. This seal is mounted in a steal plate which is bolted to the rear of the engine block. Easily search thousands of entries to find exactly what you're looking for. Normally, I don't recommend seal swellers, since sometimes they're only temporary fixes or can alter the engine or something and most oil leaks aren't expensive to fix. My concern is a non standard oil cooling system that utilizes coolant and can become blocked with sealers. Rear Main Seal The rear main seal keeps oil sealed inside the rear of the engine, where the crankshaft connects with the transmission. Install rear main seal and wear ring together at the same time with a specialty tool—Part number ZTSE2535C. It is 100% compatible. She is starting to leak oil. Our rope actually fits! anyone here had an issue similar to this? Based on your description, it sounds as though water/coolant is getting into the engine oil, creating the milky oil you are seeing. If you pop your hood and start looking around for the rear main seal, you aren’t going to have much luck seeing it. Would this product work on a vehicle using synthetic Mobil 1 oil ? On a rear wheel or 4 wheel drive vehicle the engine is mounted with its front (the side with all the pulleys and belts) towards the front of the car. © Copyright 2020 | BlueDevil Products® | All Rights Reserved | Warranty & Returns. You should expect to start seeing results after approximately 100-200 miles of driving. Engine oil and coolant leaks should not be ignored. A rear main seal, also known as a main seal or rear main bearing seal is located between the engine and transmission. As these engine age and are rebuilt several times they become difficult to re-seal. The difference would be in the location of the seal. Unfortunately, water/coolant getting into the oil would be a tell-tale sign of a blown head gasket. The cam seal is located by the timing chain cover and the rear main seal would be at the back end of the engine. If the Positive Crankcase Ventilation (PCV) system is blocked, it will increase the pressures inside the crankshaft and push out the seal. This is why you hear so many horror stories about the unbelievable costs of fixing a leaking rear main seal. The more in depth answer is: A rear main seal, also known as a main seal or rear main bearing seal is located between the engine and transmission. The best way to prove that you’ve got a rear main seal leak is to check if the engine side of the flexplate or flywheel is oily. If you are not 100% sure where the vehicle is leaking or there seem to be multiple leaks then we recommend using BlueDevil Oil Stop Leak. Is was recommended I get a second opinion on it. The transfer layer prevents wear while sealing better than a silicone or Viton material. Based on your description, we recommend using the BlueDevil Oil Stop Leak. There is truth to this statement if you use products that contain petroleum distillates. is it same as the engine oil level? The crankshaft protrudes slightly from the rear of the engine block so that it can connect to the transmission. You still only want to use the recommended amount, 1 bottle, with each application. If the rear main seal is leaking on your engine it will drip oil onto the flexplate or flywheel and sling oil around the bellhousing. Thank you for asking about your Chevy Malibu. Thank you for asking about your Dodge Magnum. Whereas the Rear Main Sealer is less concentrated and specifically formulated exclusively for leaking rear main seals. The BlueDevil will react specifically with the rubber seals and gaskets by rejuvenating and slightly expanding them. Most rear main seals have a lip that rides on the shaft. . 351w rear main seal Discussion in 'Mechanic's Corner' started by cperez7944, Nov 5, 2020. If it starts to crack or otherwise malfunction, you will be left with an oil leak. Working at Franklin Motors in 1967 – 69 era, I did numerous oil leak and rear seal replacements. The softened seal doesn’t last very long and the unfortunate side effect is that this happens to all your seals, leaving you with a bigger problem than you started with.” It is buried deep, usually under a lot of protective covers, wires, hoses and unfortunately, the bell housing of your transmission. We do not recommend adding 2 bottles at the same time; you would be better off simply retreating it with 1 bottle. Replace everything in the reverse order. The most labor-intensive seal to replace on any engine is the rear main seal. Let’s first break down the name to see what we can learn about the rear main seal. Amade of either rubber of silicone, this main seal is crucial in keeping the liquid where it should be, and typically requires a replacement to be fixed when getting … Hello, I strongly believe the real main seal is leaking from an early, rebuilt, 1950’s 8BA Ford Flathead engine. The rear main seal is a seal in your engine that is very important and usually difficult to reach. Any guidance with your product and a 1999 Toyota 4 Runner – V6? The most labor-intensive seal to replace on any engine is the rear main seal. Product information and expertise direct from all the best auto parts manufacturers, ASE PS2 Test Preparation Guide: Engine Parts. Obviously I don’t want to do any damage to my engine, but would reapply Blue Devil if it was absolutely safe to do so. It is buried deep, usually under a lot of protective covers, wires, hoses and unfortunately, the bell housing of your transmission. 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