temp sender mixup

[Jarcher3]

so i bought a 2001 larson last april.

It has the 4.3GL PEFS v6 and i have replaced a lot of the cooling system.


the issue is have been having with the engine "running hot" i have gone through before.

the engine itself is not running hot, the risers, valve covers and coolant hoses are warm but not too hot where i cant rest my hand on them.

i have done the impeller and housing. thermostat and just had my gauges rebuilt. (they should be good) i am having trouble finding the correct temp sender for this engine and if i am having THIS much trouble, i can understand why a should might be having some too.

sooo. the VP site calls for a 3850397 sender, this one has a different connector than what the boat currently has. it currently has a spade terminal. if this would correct my issue i can rewire a connector, but no one has been able to verify for me that it has the correct output reading to match the VDO gauge cluster of 37-800 or 27-500.

the shop i normally go to have used a 872068 in there with no luck for it fixing the issue.. again cant fine the OHM output range to verify..

Can anyone help me to find the correct sender, i have looked everywhere...

 

[alldodge]

The north American standard is 240 ohms (cold) and 33 ohms (hot). VDO make a north American and European standard 10 ohms (cold) and higher for (hot).

Ground the sender lead and see if the gauge pegs. If it does the you have the north standard. You can ohm the sender to see what it shows. As for the spade terminal, I would suggest changing to the single stud. Easy enough to find, just need to know what size hole it goes into

 

[Bondo]

the engine itself is not running hot, the risers, valve covers and coolant hoses are warm but not too hot where i cant rest my hand on them.

Ayuh,..... So what's the problem yer tryin' to fix,..??

You wanta change the sender, yet don't say what the gauge is readin',....

 

[Jarcher3]

No Title

The gauge is reading at the red end of the temp gauge, and sounding a overheat alarm occasionally.

i want to be able to look at the gauge and reliably know the temp of the engine.

So when i run the engine this is right about where it sits. now i feel okay with this knowing that the temp in the engine isn't this high but i do want to have it be accurate.

it has a 160deg thermostat. btw


I will take a look at grounding it.

now after looking into the VDO troubleshooting again, i noticed that the cluster is able to run on either a US standard Sender or a VDO

VDO is 27-500 ohm
US standard 37-800 ohm.

if it was set for a VDO running a standard would that cause it to read consistently yet easily overheat with the differnce in max of 300Ohm?

apparently i can go in and change the sender preference.

 

[alldodge]

VDO is 27-500 ohm
US standard 37-800 ohm.

Think you transposed the numbers The US standard if anything should be 800-37 not 37-800

I have vdo gauges on my cruiser and they use the us standard, have replaced the fuel gauge and same ohm range

 

[Bondo]

The gauge is reading at the red end of the temp gauge, and sounding a overheat alarm occasionally.

Ayuh,..... That kinda says the motor is in fact gettin' Hot,..... Don't it,..??

Yer gauge reads the Sender,....
The alarm is an entirely different circuit, with a temp Switch, all it's own,....
That's 2 separate systems says it's Hot,....

Just sayin',..............

 

[Jarcher3]

here is where i pulled my numbers, go to technical support> technical support documents>VDO Instrument Clusters Installation and Troubleshooting Guide

as far as the temp sender and switch, i believe there is only one. the sender reads and when over a certain resistance, sends for the alarm, it doesn't have a separate switch from the sender. (at least that's what I've been reading)

 

[alldodge]

You do have a temp switch (item 22) and temp sender (item 21), switch to alarm and sender to gauge
https://www.marinepartseurope.com/en/volvo-penta-explodedview-7744270-30-8815.aspx

 

[Jarcher3]

^thanks for that!!! i hadnt found where the shop got the number for that. do you know where the switch is housed? i have the sender in the thermostat housing.


Also, is it possible that the sender sends a alarm to the cluster and the switch sends the alarm to the engine alarm? because i do have both....

 

[alldodge]

^thanks for that!!! i hadnt found where the shop got the number for that. do you know where the switch is housed? i have the sender in the thermostat housing.

No, but it should be around the thermostat or intake manifold.

Also, is it possible that the sender sends a alarm to the cluster and the switch sends the alarm to the engine alarm? because i do have both....

Yes, totally possible. Maybe that's why you have a different then normal sender, don't know

 

[muc]

The VDO cluster has proven itself to be very troublesome. VDO dropped all support years ago. Almost all of the boat manufacturers that used this cluster sell a complete dash kit to convert it to analog gauges.

I think CDI stopped trying to repair them a few years ago, but I'm not sure. Due to all the problems servicing these, the last two marina's I worked for will no longer work on them --- only install a complete dash. Not a cheap option.

I'm not sure what your problem is but based on past experience this is how they start to die (one of the gauges will start to read high or low and set off a alarm) sometimes adding a better ground to the controller will help for awhile. You might want to try running a 10 ga. wire from the ground stud on the engine that the negative battery cable is connected to to main plug on the controller. You can Ohm your existing temp sender to see if it's working right. If you replace it, it's best to go with the "default" sender.