280GE M110 compression readings
Simple question, I think....
What compression readings (in PSI pls) should I get on this engine?
Thanks
The Ideal is between 140-165 psi
The figures i have given are for a new H/C engine so an older engine will have less, the compressions need to be measured at cranking speed with wide open throttle, a hot engine will be more loose but the main concern is if there is a major difference between the cylinders rather than if they are even ish and the reading is low, Have you got a specific fault you are looking for ?
On the contrary, David mentions that more compression is lost when taking hot engine readings, in fact it should be lesser as the internal should have expanded making a better seal hence better compression readings are got. The difference of 10% is allowed between cylinder readings overall.
In a particularly low reading cylinder squirt a little engine oil into the cylinder and take another reading, should a better read be achieved then obviously this indicates some internal wear. Generally and theoretically all cylinders should have a similar reading within 10 % difference between the low and highest reading.
Pedantically, compression should be taken after making sure the valve clearances are checked and adjusted as necessary - adjusting the valves is best done on a cold engine.
I don't know the compression pressure off hand but one point to note that saloon and G-Wagen engine have different compressions. G-Wagen engine are usually of lower compression than the saloons engines. If you are sure your's is the original G-Wagen engine then it is the low compression readings you will want.
the M110.981 280e car engine pumped out 185 bhp whereas the G-Wagens M110.994 unit had a more modest 150 bhp, but pre 1984 engines had 156 bhp
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
Hi David
Engine is out of the car and being tested on the bench - do those readings change if it's a cold engine?
Thanks