Date: Thu, 15 Apr 2021 22:55:47 +0000
Reply-To: Dennis Haynes <d23haynes57@HOTMAIL.COM>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: Dennis Haynes <d23haynes57@HOTMAIL.COM>
Subject: Re: oil in coolant
In-Reply-To: <CAMjSMWsPRUzaS82t65DacHvFe9ymJHcmDuy=e_6R8OBCOxytYQ@mail.gmail.com>
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A leak down test will give a leakage indicator and then full shop pressure into the cylinder will show where the failure is, valves, rings, or also a leak into the coolant system, cracked or loose head.
Dennis
From: Ryan Cresawn <jrcresawn@gmail.com>
Sent: Thursday, April 15, 2021 6:16 PM
To: Dennis Haynes <d23haynes57@hotmail.com>
Cc: vanagon@GERRY.VANAGON.COM
Subject: Re: oil in coolant
I appreciate everyone's replies. Dennis, you gave me a lot to think about. Thank you. I know it's been quite a while since I've provided an engine update. So here goes. I checked the compression following the instructions in the Bentley service manual and the results are disappointing.
Cylinder #1 = 141 PSI
Cylinder #2 = 126 PSI
Cylinder #3 = 96 PSI
Cylinder #4 = 136 PSI
I have noticed that each year since 2017 when I have the emissions tested in Tucson that the CO% increases. I have read that oil burned in the combustion chamber due to worn piston rings and/or cylinders can cause excessive CO% in emissions. I doubt the Vanagon will pass the emissions test in August when it is due so I'm considering my options. What is the most likely cause of low compression in cylinder #3? I feel confident the overheating event is a factor.
Thanks as always,
Ryan
On Sun, Jan 3, 2021 at 8:27 PM Dennis Haynes <d23haynes57@hotmail.com<mailto:d23haynes57@hotmail.com>> wrote:
So a few things. The reason that low coolant generates a red light in the center of the gauge and loos of water pump/alternator drive turns on that tred light is that both are critical failures which require an immediate shut down as soon as it is safe to do so. As the temp gauge sensor is mounted on a plastic housing and not as part of the head it relies on coolant flowing in order for it to work. Even still it's response is damped both for speed and temp change indication. Simply put, once the water pump stops turning the gauge will not rise until after you make steam and engine damage is occurring. Driving 5 miles you have pulled studs, possibly cracked or warped the heads and damaged the seal at the top of the cylinders.
In this condition the relief at the pressure cap just doesn't have enough capacity to vent all the pressure. The pin holes in the coolant loop are due to excessive temperature and pressure. Consider that every hose and plastic junction along with the radiator and heater cores have been exposed to this trauma. My rule of thumb is continued operation after a cooling or lubrication system failure cost $1K per mile until you need the tow truck anyway.
It is also likely that this event damaged the oil cooler so you may have it passing oil into the coolant. If you don't have the means to actually test both sides under pressure just replace it. Also replace the thermostat and if still plastic housing remove and inspect it for damage/cracking.
For the belt failure most likely it was the water pump/alternator belt that went first. The belts available just suck for this application and few properly tension them. This belt drive is very poorly designed and it frequently fails.
Regarding the GoWesty kit I don't recommend this as it still uses plastic fittings. I use all brass tess and threaded fittings/hose barbs for the connection to the tank. Silicone coolant hose makes this a near lifetime repair. For mounting I use the tie wraps with the Christmas tree or pin mounting using the existing holes maybe adding a couple more. As part of upgrading the system get rid of that plastic coolant pressure tank and replace with the Van Café or GoWesty aluminum tank. Besides the tank itself getting a pressure cap that is common, can be visually inspected, along with a design where both a cpa and system pressure tester can be easily used is worth the cost of admission.
After you think you have it all sorted after 500 miles or so have the oil tested. Coolant getting into the oil become destructive to the bearings long before it become visible. After an overheat coolant can get into the oil due to the cylinder becoming loose and coolant seeping under them and also under the head nuts. The top studs/nuts will leak externally but the lower ones under the rocker shafts will go into the oil.
Hope this helps.
Dennis
From: Ryan Cresawn <jrcresawn@gmail.com<mailto:jrcresawn@gmail.com>>
Sent: Sunday, January 3, 2021 1:13 PM
To: Dennis Haynes <d23haynes57@hotmail.com<mailto:d23haynes57@hotmail.com>>
Subject: Fwd: oil in coolant
Hi Dennis,
I sent this message to the Vanagon mailing list yesterday, but I think it might not be working. If you have time to reply I sure would appreciate it.
With sincere gratitude,
Ryan
---------- Forwarded message ---------
From: Ryan Cresawn <jrcresawn@gmail.com<mailto:jrcresawn@gmail.com>>
Date: Sat, Jan 2, 2021, 11:47
Subject: oil in coolant
To: Vanagon List <vanagon@gerry.vanagon.com<mailto:vanagon@gerry.vanagon.com>>
The water pump/alternator V-belt failed on my 1991 Vanagon (2.1L engine). I drove 4.8 miles home. When I parked steam was coming from the engine compartment. I discovered that the A/C compressor belt also broke. I believe the A/C belt broke first and then that broken belt got caught between the water pump/alternator belt and a pulley which caused it to break. The steam was caused by coolant spraying on the engine from a hole smaller than a BB in the white plastic coolant bleed ring. I believe that hole was caused by either excessive heat or impact from one of the broken belts. I have assessed the damage and begun repairs.
I have replaced the leaking coolant bleed ring with this kit from GoWesty:
https://www.gowesty.com/product/bundles-and-kits/24210/coolant-bleed-ring-replacement-kit<https://na01.safelinks.protection.outlook.com/?url=https%3A%2F%2Fwww.gowesty.com%2Fproduct%2Fbundles-and-kits%2F24210%2Fcoolant-bleed-ring-replacement-kit&data=04%7C01%7C%7Cd7df6bf4c49f47ec160d08d9005c0555%7C84df9e7fe9f640afb435aaaaaaaaaaaa%7C1%7C0%7C637541217487124330%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C1000&sdata=guoB8lM9gBpu4v%2BMmA9VtlC5eYduK0lm2Z%2BGcSN16eo%3D&reserved=0>
I did not follow their instructions entirely. They supply self-tapping screws they propose I fasten to painted sheet metal in the engine compartment. My assumption is that will cause rust. Instead, I purchased two 3/8-inch oak dowel rods and cut them to length. They fit perfectly in the white plastic clips that held the original coolant bleed ring. Then I used zip ties to attach the rubber hose to the dowel rods. I like the final result.
I blew on the 16-PSI blue coolant cap and it would not make the trumpet sound so I replaced it with a new one. I put a washing machine flood tray under the engine and found a coolant leak. It was at the Temp II sensor. I removed the sensor and found the O-ring was dry. I replaced it with a new one. I also polished the sensor with Brasso and coated the O-ring with a thin layer of dielectric grease. I installed new belts. I made a "Libby bong" and followed the fill procedure. There were no external coolant leaks. I then started the engine and drove five laps around the block. I have oil temperature and pressure gauges. I noticed on my drive that the coolant and oil temperatures began to rise and the oil pressure, which started high, began to fall. Everything seemed good, but I still needed to look for coolant and oil mixing. I extracted about 8 ounces (250 mL) of coolant from the pressurized coolant tank with the blue cap. I let the coolant sit in my house for a week and eventually noticed a tiny film on top of the coolant which I assume is oil. I can provide photos if anyone is curious. Two days ago I leveled the Vanagon and let it set overnight. Then yesterday morning I let about 1-2 ounces of oil drain from the drain plug into a glass beaker. I found no coolant in the oil.
I searched the mailing list archives and found a thread about oil being found in coolant. It looks like Dennis Haynes wrote in 1996 that 95% of "oil in coolant" problems are caused by a bad oil cooler. If the Gerry website were up I would provide a link to his post. I bought a new oil cooler but have not replaced it yet. I drained the oil yesterday. My next step is to drain the coolant. I will then remove the oil filter and then the oil cooler. My plan is to install the new oil cooler and then add fresh oil and coolant. Should I test the oil cooler I plan to remove from the engine? If I find oil in the coolant after replacing the oil cooler and fluids where should I look next?
Many thanks,
Ryan
