Check the Solr Config file for the limit
<maxFieldLength>10000</maxFieldLength>
This would limit the field length, which might be causing issues for you.
Which version of solr are you using, as it might have been deprecated.
The maxFieldLength parameter was removed in Solr 4. If restricting the length of fields is important to you, you can get similar behavior with the LimitTokenCountFactory, which can be defined for the fields you'd like to limit. For example, would limit the field to 10,000 characters.