Noisy tappets
I have a W463 with an OM603 D30 engine - a 300GD in other words! It's driving me to drink as my generally helpful but so far unsuccessful dealer has been unable to help me with this problem.
The problem is that the tappets get noisy when the vehicle is driven at highish speeds (±60mph) for 5 - 10 minutes. Gentle driving after that quietens them to normal after a short while.
The problem is that they were just fine until an oil change was done. Now this is the mysterious part as nothing apart from the filters and oil was replaced. The oil pressure is normal. Any ideas???
Some background: the engine was overhauled a few months back (at 180k miles) and persistent noisy tappets (and low oil pressure) was cured by replacing the sprocket for the (new) oil pump with a smaller one - this despite the original sprocket being OK for the engine for all those miles. This cured the oil pressure problem and quietened the tappets. The tappets are new too.
Now an oil change has things back at square one.
Please help as I'm getting desperate!
When you say that the tappets were replaced, what do you mean?
I had noisy (slightly) tappets and replaced the hydraulic elements. This fixed the problem entirely.. Is this what you had changed?
I can see no reason to change the gear on the oil pump. The manual says you should have 3bar at 1500 rpm with hot oil. The other variable is the type of oil you put in it. But if you have full pressure the hydraulic elements should be working correctly.
Is the cam in good condition?
Get the oil changed again for what it costs without the filter, if they have used a very light oil like mobil 1 it may cause some noise, try a cheaper but thicker oil??
Thanks for the replies.
To answer some of the questions:
The hydraulic tappets are new and so is the cam.
The gear seems to have made a big difference as there was very little pressure at idle with hot oil - less than 1 bar. Now it is within the range as indicated in the owner's manual.
I think I need to check the oil filter as I don't know which one they have used and if it has an internal valve of sorts. Plus I'll change the oil and let you know what happens. At one point the dealership said that the truck oil they were using was thinner than the passenger car oil. When asked what grade they were using I was told 15W40, which is correct, but I will try with something else next now.
Hello GuySA
Did you get the problem sorted?
The problem is solved now. I planned to replace the filter and oil and did one at a time starting with the filter. A new filter did the trick. Not sure why though as they look similar and have the same part numbers? Both sourced from the MB agent. It's a mystery...
Thanks for the suggestions.
JOIN THE GWOA
This website and forum are provided for the benefit of enthusiasts and owners of all Mercedes Benz off road vehicles, in particular the G Wagen. The costs of development, upkeep and provision of the site are met entirely by the annual subscriptions of club members. If you are using the site and are not a member of the G Wagen Owners Association please consider joining. You will have access to areas on the site that are not open to non members, to club trips and meetings and to technical assistance. In addition your contribution (only £25 annually) will help us maintain and develop our website for future users.
Who's new
- Jaffa_JIM_23
- Wrabstar
- GG
- KTMSCANIA22
- 280ge
What sort of Oil Filter have they fitted? Genuine or Mann are best?
Isn't there some valve in their?